Security Response

Contribution: Takayoshi Nakayama

I was going through some files we acquired related to targeted attacks the other day and an unusual set of files caught my eyes. We did some analysis on the files and it turns out a pair of files in the set exploits a vulnerability we have not seen in the wild before. Microsoft is aware of the issue and notes users who have applied MS11-073 are fully protected.

The files stand out from the common targeted attacks because a Microsoft Word document file is paired with a .dll file. Usually, targeted attacks involve one file which drops malware. The pair would most likely arrive to the target wrapped in an archive file attached to an email. It is common to see document files sent by email inside an archive, but typically, you would not see .dll files ever sent by email.

The exploit makes use of an ActiveX control embedded in a Word document file....

Thanks to Eric Chien for his assistance with this research.

Introduction

We recently came across a new piece of Android malware, first highlighted by NC State’s Xuxian Jiang, and began investigating the command-and-control (C&C) servers associated with the threat. The malware was discovered on a third party marketplace (not the Android Market) and is bundled with a legitimate application for configuring phone settings. Trojanized applications are a well known infection vector for Android malware, as they allow malware to be distributed while retaining the appearance of a legitimate application.

Analysis of these servers indicate the total number of infected devices connected to the botnet over its entire life span numbered in the hundreds of thousands. The number of infected devices able to generate revenue on any...

At 3 AM, on February 6, 2012, Symantec Security Response observed spam carrying malicious links which target the upcoming tax season. The spam volume spiked between 6 AM and 1 PM, identifying over 200 unique URLs which lead to a Blackhole toolkit.

A Blackhole toolkit compromises the machine by targeting various vulnerabilities on the victim's machine. Symantec protects our customers with multiple-layer protection of antispam, antivirus, and IPS signatures. The payload downloaded from the malicious website is detected as Trojan.Zbot, for instance, and IPS detects this web attack as “Web Attack: Blackhole Toolkit Website 14” and “...

For quite some time, we have observed the technique of server-side polymorphism being used to infect Windows computers around the world. What this means is that every time a file is downloaded, a unique version of the file is created in order to evade traditional signature-based detection. We are now seeing this same technique being used for malicious Android applications hosted on Russian websites. We detect all of these variants as Android.Opfake. The sites hosting Opfake include either links or buttons that can be used to download the malicious packages that are purporting to be free versions of popular Android software.

The applications morph themselves automatically in a few ways every time the threat is downloaded. In addition, manual modifications are also made every few days indicating that the malware authors are actively maintaining this malware family.

Opfake...