Hacktivity 2018 badge - quick start guide for beginners

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

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: 

1. 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.
2. Restart the same level, attach Cheat Engine to the game's process
3. Scan the memory for the same value at the beginning of the race
4. 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.
5. Change the values (both the real one and some false positives) to something big
6. Watch the game to crash
7. 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!

DSploit

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:

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

If you are a user:

1. Don't trust sites with your confidential data if the above points are not fixed. Choose a more secure alternative
2. Use HTTPS everywhere plugin
3. 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

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:

1. You have 1095 USD + VAT + shipping to buy this Pwn Pad
2. 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:

1. Start the Wifite app
2. Choose your adapter (the USB WiFi)
   
   
   
3. Choose the target network (wep_lan in the next example)
4. Wait for a minute 
5. 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!

Hacking Windows 95, part 1

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:

1. 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!
2. Only hacks without user interaction are allowed (IE based sploits are out of scope).
3. 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.
4. 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.