RIG Exploit Kit (March 9th, 2016)

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Dell Sonicwall Threat Research team has observed Rig Exploit kit, using exploits for Adobe Flash and IE vulnerabilities in its arsenal.

Redirection Chain:

Malicious javascript code is injected into compromised website to redirect victim to Kit’s Landing page.

Fig-1 : Compromised webpage with injected Javascript

This exploit kit uses Iframe redirection technique as shown below:

Fig-2 :Injected script has an iframe pointing to Kit’s landing page.

Exploit Kit’s landing page contains three HTML script elements as shown below:

Fig-3 : Kit’s Landing Page

First script element defines two custom variables. The next two scripts are used to decrypt data and add new HTML script elements.

The purpose of the data decrypted by the second script element is to play a malicious flash file, which exploits Adobe Flash vulnerability [CVE-2015-8416], as shown below:

Fig-4 : Decrypted data of second script

Similarly, the data decrypted by the third script tag, exploits vulnerability present in IE [CVE-2015-2419] as shown below:

Fig-5 : Decrypted data of third script

Fig-6 : packet capture with URI pattern

Sonicwall Gateway AntiVirus provides protection against this threat via the following signatures:

  • GAV: RigHtm.EKA (Exploit)
  • GAV: RigSWF.EKA (Exploit)

Security News
The SonicWall Capture Labs Threat Research Team gathers, analyzes and vets cross-vector threat information from the SonicWall Capture Threat network, consisting of global devices and resources, including more than 1 million security sensors in nearly 200 countries and territories. The research team identifies, analyzes, and mitigates critical vulnerabilities and malware daily through in-depth research, which drives protection for all SonicWall customers. In addition to safeguarding networks globally, the research team supports the larger threat intelligence community by releasing weekly deep technical analyses of the most critical threats to small businesses, providing critical knowledge that defenders need to protect their networks.