TROJ_MEREDROP.ZA

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.

Arrival Details

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

Installation

This Trojan drops the following component file(s):

• %Application Data%\Help\iexplore.exe - Detected as TROJ_AGENT.WAWB
• %User Temp%\alg.exe - Detected as TROJ_AGENT.WAWB

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

It drops the following non-malicious files:

• %Temp%\{random name}.xls

(Note: %Temp% is the Windows Temporary folder, which is usually C:\Windows\Temp.)

Dropping Routine

This Trojan takes advantage of the following software vulnerabilities to drop malicious files:

• CVE-2009-3129

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

NOTES:

It opens the file %User Temp%\{random name}.xls to trick users into thinking that it is a normal Excel file.