Paper: Prosecting the Citadel botnet - revealing the dominance of the Zeus descendent: part two

Posted by   Virus Bulletin on   Sep 11, 2014

Aditya K. Sood and Rohit Bansal study the malware's behaviour when ran on a physical machine.

Last week, we published the first part of the paper 'Prosecting the Citadel botnet - revealing the dominance of the Zeus descendent'. In it, researchers Aditya K. Sood and Rohit Bansal looked at the design and implementation of the infamous Citadel botnet, as well as the admin panel used by Citadel's botheders.

Today, we publish the second part of the paper. In it, Aditya and Rohit analyse a new sample of the malware. Obtaining suh as sample wasn't trivial, as the malware targets only certain countries and regions and they had to try various VPN servers in different locations before they were successful.

Then they allowed the malware to install, initially in a virtual environment. However, this failed: rather than connecting to the real command and control server, Citadel made various bogus DNS requests in an attempt to confuse researchers. This behaviour is common in today's malware; we wrote about it in much detail a few weeks ago, when we previewed James Wyke's VB2014 paper.

  Bogus DNS traffic sent when the botnet detects it is running inside a virtual environment.

Although far more cumbersome, there is always the option to run the malware on a physical machine. Once they had done that, the researchers were able to capture the traffic the malware made to its C&C server to download the configuration file, after first making sure it was allowed to do so.

In a move which is not uncommon for modern malware, Citadel contains a separate dropper that removes itself once the actual malware is installed. The malware creates an entry in the registry to maintain persistence following reboots. It performs API hooking to conduct its primary function: man-in-the-browser attacks to steal and alter HTTP requests and responses.

The paper concludes with a signature for the Snort IDS, that should help administrators detect Citadel infections on their network, based on the C&C traffic.

The second part of the paper can be viewed here, while a PDF of the full paper can be downloaded here.

Posted on 11 September 2014 by Martijn Grooten

twitter.png
fb.png
linkedin.png
hackernews.png
reddit.png

 

Latest posts:

VB2020 localhost call for last minute papers: a unique opportunity

Why VB2020 localhost presents a unique opportunity for you to share your research with security experts around the globe.

VB2020 localhost call for last-minute papers now open!

The call for last-minute papers for VB2020 localhost is now open. Submit before 17 August to have your paper considered for one of the nine slots reserved for 'hot' research!

Announcing... VB2020 localhost

Announcing VB2020 localhost: the carbon neutral, budget neutral VB conference!

VB2019 paper: APT cases exploiting vulnerabilities in region-specific software

At VB2019, JPCERT/CC's Shusei Tomonaga and Tomoaki Tani presented a paper on attacks that exploit vulnerabilities in software used only in Japan, using malware that is unique to Japan. Today we publish both their paper and the recording of their…

New paper: Detection of vulnerabilities in web applications by validating parameter integrity and data flow graphs

In a follow-up to a paper presented at VB2019, Prismo Systems researchers Abhishek Singh and Ramesh Mani detail algorithms that can be used to detect SQL injection in stored procedures, persistent cross-site scripting (XSS), and server‑side request…

We have placed cookies on your device in order to improve the functionality of this site, as outlined in our cookies policy. However, you may delete and block all cookies from this site and your use of the site will be unaffected. By continuing to browse this site, you are agreeing to Virus Bulletin's use of data as outlined in our privacy policy.