Analysis by: Karl Dominguez
 PLATFORM:

Windows 2000, XP, Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Trend Micro has flagged this malware as noteworthy due to the increased potential for damage, propagation, or both, that it possesses. Specifically, it exploits an unknown vulnerability in Adobe Reader and Acrobat to drop another malicious file.

To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

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: 763,188 bytes
File Type: PDF
Memory Resident: No
Initial Samples Received Date: 08 Sep 2010
Payload: Drops files

Arrival Details

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

Autostart Technique

This Trojan drops the following files:

  • %User Temp%\hlp.cpl - detected as TROJ_DLOADR.WM

(Note: %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.)

Dropping Routine

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

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

Other Details

This Trojan is a zero-day exploit for the following vulnerability:

  • Adobe Reader
  • Adobe Acrobat

More information on this vulnerability can be found below:

  • Adobe Security Bulletin APSA10-02

It does the following:

  • Exploits CVE-2010-2883, which exists in Adobe Reader and Acrobat 9.3.4 and earlier versions, that could cause a crash and potentially allow an attacker to execute arbitrary commands on the affected system

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.446.02
FIRST VSAPI PATTERN DATE: 08 Sep 2010
VSAPI OPR PATTERN File: 7.447.00
VSAPI OPR PATTERN Date: 08 Sep 2010

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Remove malware files dropped/downloaded by TROJ_PIDIEF.WM

Step 3

Scan your computer with your Trend Micro product to delete files detected as TROJ_PIDIEF.WM. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

Step 4

Download and apply these security patches Refrain from using these products until the appropriate patches have been installed. Trend Micro advises users to download critical patches upon release by vendors.


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