Analysis by: Marfel Tiamzon
 PLATFORM:

Windows 98, ME, NT, 2000, XP, Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Trojan may be downloaded by other malware/grayware/spyware from remote sites. However, as of this writing, the said sites are inaccessible.

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: 2,290 bytes
File Type: PDF
Memory Resident: Yes
Initial Samples Received Date: 05 Aug 2010
Payload: Downloads files, Drops files

Arrival Details

This Trojan may be downloaded by other malware/grayware/spyware from remote sites.

However, as of this writing, the said sites are inaccessible.

Dropping Routine

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

  • Adobe Reader 'util.printf()' JavaScript Function Stack Overflow Vulnerability

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

Download Routine

After successfully exploiting the said vulnerability, this malware connects to the following URLs to possibly download other malicious files:

  • hxxp://{BLOCKED}.{BLOCKED}.44.90/d/l.php?i=5

Other Details

Based on analysis of the codes, it has the following capabilities:

  • Downloads the file, %User Temp%\dfupd.exe
  • Takes advantage of the software vulnerability(ies), Adobe Reader 'util.printf()' Javascript Function Stack Buffer Overflow Vulnerability to drop possibly malicious files

(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.)

  SOLUTION

Minimum Scan Engine: 8.900

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

Scan your computer with your Trend Micro product to delete files detected as TROJ_PIDIEF.WKQ. 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 3

Download and apply this security patch 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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