Analysis by: Alvin Bacani
 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, Dropped by other malware

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size: 14,905 bytes
Memory Resident: Yes
Initial Samples Received Date: 08 Oct 2013
Payload: Downloads files

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Download Routine

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

  • http://{BLOCKED}.31.154/mii/fird.gif

It saves the files it downloads using the following names:

  • %User Temp%\main001.gif - detected as TROJ_INJEK.XPL

(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, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

Other Details

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

  • MS13-080

NOTES:

It checks if the following path exists:

  • %Program Files%\Kaspersky Lab

If the path is detected, it will not proceed with its routines.

It checks for the following AV-related registries and uninstall the related software once found:

  • HKEY_LOCAL_MACHINE\Software\Ahnlab\V3Lite
  • HKEY_LOCAL_MACHINE\Software\V3 365 Clinic
  • HKEY_LOCAL_MACHINE\Software\NHN Corporation\NaverVaccine
  • HKEY_LOCAL_MACHINE\Software\ESTsoft\ALYac

  SOLUTION

Minimum Scan Engine: 9.300

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Search and delete these files

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Temp%\main001.gif

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.  

  • http://technet.microsoft.com/en-us/security/bulletin/ms13-080

Step 4

Scan your computer with your Trend Micro product to delete files detected as HTML_SHELLCD.XPL. 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.


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