Behavior Analysis Stops Romanian Data-Stealing Campaign

[Nytro]

Behavior Analysis Stops Romanian Data-Stealing Campaign

By Ankit Anubhav , Christiaan Beek on Dec 03, 2014

In a recent press announcement, McAfee and Europol’s European Cyber Centre announced a cooperation of our talents to fight cybercrime. In general these joint operations are related to large malware families. Writing or spreading malware, even in small campaigns, is a crime. McAfee Labs doesn’t hesitate to reach out to its partners and contacts in CERTs and law enforcement. In the following case, a new Romanian-based data-stealing campaign was caught early due to behavioral and data analytics.

In our sample behavioral database, we found a new site hxxp://virus-generator.hi2.ro. Visiting the link revealed an open directory that allowed us to browse the content:

Often we observe that malware authors become overzealous in attacking victims, and forget to protect their own malware servers. Despite this campaign’s effectiveness, the malware authors took very little care to ensure that they themselves were not breached.

The binaries, which help us to understand how this campaign works, are injector.exe and blurmotion.exe. As the name suggests, injector.exe compromise the victim’s system via code injection in Internet Explorer. It first disables the firewall to ensure a smooth connection to the malware control server.

With the help of the mget command, the malware connects control site and downloads the payload blurmotion.exe.

The fact that the malware site doesn’t use any authentication makes sense because it leads to a swift connection between the victim and the attacker. Once the payload is downloaded, the batch file root.vbs takes over. This batch file is dropped by injector.exe and ensures that blurmotion.exe is executed.

We see the use of wscript.sleep 30000, which makes sure no activity happens for 5 minutes. This could be an attempt to deceive malware analyzers that the sample won’t do anything. Necessary run entries make sure root.vbs runs. After that a misspelled “restartt” is forced.

After this step, the system goes into a forced restart, and by this time the work of injector.exe (to download and install the payload) is done. From here the payload takes over. Blurmotion.exe, like its parent, drops a batch file to perform malicious activities.

Blurmotion takes the username of the victim and dumps all the processes running in the victim’s system with the name %usename%.ini.

Once the stolen data is logged, the malware uploads it to the control server via the mput command. We can see “echo cd BM” used in commands. This is the same BM folder on the malware control server that stores the logs of all victims. Like the payload, this stolen data is exposed to anyone who finds the malware control server. Our test virtual machine “victim” was named Klone, and we found it quickly uploaded on the control server.

The size of Klone.ini is zero because we had reverted to the virtual machine before the malware could steal data. In all the other infected user logs, we can see the malware executable blurmotion.exe running, confirming that those systems had been compromised.

We can also see repeated connections made to a specific site (mygarage.ro), possibly an attempt to increase its traffic. The author is so aggressive that he or she even tried to overclock the CPU to bring more traffic to this site.

The author succeeded in these attempts. In our internal behavioral database we found a lot of redirects to this site.

McAfee detects these payloads as Rodast. McAfee SiteAdvisor also warns against connecting to this site:

Because the campaign was based in Romania, McAfee Labs contacted the Romanian CERT. After we discussed the approach and strategy with them, the Romanian team took the appropriate actions, and gave us permission to publish our analysis of the campaign in this article.

Malware authors sometimes act carelessly, and assume that they are safe if no one detects them. But data from behavioral analysis, along with cooperation with CERTs and law enforcement, can find live campaigns and stop them.

Sursa: Behavior Analysis Stops Romanian Data-Stealing Campaign | McAfee

Edited December 4, 2014 by Nytro