Document with VBA Macro drops a variety of malware (Jan 15th, 2016)

By

The Dell Sonicwall Threats Research team has received reports of a Microsoft Word document file containing a malicious VBA script. This dropper Trojan has been around for a while in various different forms and drops malware from a variety of different families.

Infection Cycle:

The Trojan arrives as a MS Word Document file:

Quick analysis of the doc file shows the presence of a VBA macro and references to a remote webserver containing an executable file:

Once opened, the following document is shown in MS Word:

The document encourages the user to enable the malicious macro as the document has “incorrect encoding”. Once the macro is executed it causes the download of a malicious executable file:

The Trojan adds the following files to the filesystem:

  • %USERPROFILE%Local SettingsTemppcampaniliformgoodfellow.exe [Detected as GAV: Upatre.JO (Trojan)]

The file downloaded in the case was a variant of the Upatre Trojan. It exhibits the usual encrypted traffic:

It has been reported by other vendors that variants of this Word Document also drop malicious files from other malware families.

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

  • GAV: Upatre.JO (Trojan)
  • GAV: Downloader.ANZ (Trojan)
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.