Research

Liniaal – Empire through Exchange

Getting access to an internal network is always great, keeping this access can be a whole other challenge. At times we want to fly below the radar and ensure our access doesn’t get detected or blocked by traditional network based solutions. To this end, communicating directly through an Exchange server can be very beneficial and solve both challenges. Ruler provides us with a means of getting a shell on an internal network.…

USaBUSe Linux updates

(If you’re new to this project, read the intro first) For the past few months, I’ve been working on porting the USaBUSe stack from the custom hardware (AVR+ESP8266) to the Linux USB gadget stack. I wanted to make the techniques more accessible to people unfamiliar with embedded development, and I also wanted to take advantage of the variety of possibilities inherent in having a fully featured Linux environment to work…

Exploiting MS16-098 RGNOBJ Integer Overflow on Windows 8.1 x64 bit by abusing GDI objects

Starting from the beginning with no experience whatsoever in kernel land let alone exploiting it, I was always intrigued and fascinated by reverse engineering and exploit development. The idea was simple: find a 1-day patch with an exploitable bug but with no proof of concept exploit currently available, in order to start my reverse engineering and exploit dev journey with.Now the bug discussed here was not my initial choice: I…

Rattler:Identifying and Exploiting DLL Preloading Vulnerabilities

In this blog post I am going to describe a new tool (Rattler) that I have been working on and discuss some of the interesting anomalies found while building it. Rattler can be found on our Github repo and was recently discussed at BSides Cape Town. Rattler helps identify which application DLL’s are vulnerable to DLL preloading attacks. In a nutshell, DLL preloading attacks allow you to trick applications into…

Kwetza: Infecting Android Applications

This blog post describes a method for backdooring Android executables. After describing the manual step, I will show how to do the same with a new tool, Kwetza, that I’m releasing today. Infecting Android applications provides a great way to determine the impact and affect of the malicious activities we see in the wild, from ransomware to practical jokes. This not only provides you with an entry point onto user devices,…

PowerShell, C-Sharp and DDE The Power Within

aka Exploiting MS16-032 via Excel DDE without macros. The modified exploit script and video are at the end. A while ago this cool PowerShell exploit for MS16-032 was released by FuzzySecurity. The vulnerability exploited was in the secondary login function, which had a race condition for a leaked elevated thread handle, we wont go into much details about the vulnerability here though. It is a really awesome vulnerability if you want to…

DET – (extensible) Data Exfiltration Toolkit

Often gaining access to a network is just the first step for a targeted attacker. Once inside, the goal is to go after sensitive information and exfiltrate it to servers under their control. To prevent this from occuring, a whole industry has popped up with the aim of stopping exfiltration attacks. However, often these are expensive and rarely work as expected. With this in mind, I created the Data Exfiltration…

Understanding Locky

A few days ago I was asked to have a look at the newly emerged crypto-ransomware threat “Locky” which utilises Dridex-like Command and Control (C&C) communications techniques. For some background reading, I recommend you read the following: http://sensorstechforum.com/aes-128-encryption-employed-by-locky-ransomware/ https://nakedsecurity.sophos.com/2016/02/17/locky-ransomware-what-you-need-to-know/) http://www.theinquirer.net/inquirer/news/2447460/dridex-style-locky-ransomware-is-infecting-machines-via-microsoft-word It looks like a new (FEB2016) addition to the crypto-ransomware family : 1. Dirty Decrypt 2. CryptoLocker 3. CryptoWall / Cryptodefense 4. Critroni / CTB Locker 5. TorrentLocker 6. Cryptographic Locker 7. TeslaLocker 8. Locky…

Sensepost Maltego Toolkit: Skyper

Collecting and performing Open Source Intelligence (OSINT) campaigns from a wide array of public sources means ensuring your sources contain the most up to date information relating to your target. Skype, with over 300 million users, can be a vital source if used correctly. The above graphic shows over 70 million active members and over 500 million users that have registered!. As with all things online, many users leak sensitive…

(local) AutoResponder

When doing internals, usually an easy first step is to use Responder and wait to retrieve NTLM hashes, cracking them and hoping for a weak password. The problem is that sometimes fancy cracking rigs might not be available, it might be a mess to copy/paste all those hashes, send them, wait for an answer where you could already do some work locally, without any effort. We’re all lazy, and I’m even more…