W2KM_ZBOT.YUYAMW

 Analysis by: Rhena Inocencio

 ALIASES:

Trojan-Downloader.VBS.Agent.bcq (Kaspersky), W97M/Dropper.ao (McAfee)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It executes the dropped file(s). As a result, malicious routines of the dropped files are exhibited on the affected system.

  TECHNICAL DETAILS

File Size:

1,010,688 bytes

File Type:

DOC

Initial Samples Received Date:

21 Jan 2016

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\barriers.exe

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It executes the dropped file(s). As a result, malicious routines of the dropped files are exhibited on the affected system.