Analysis by: Abraham Latimer Camba
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This backdoor 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: 217,088 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 13 Jan 2010

Arrival Details

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

Installation

This backdoor drops the following files:

  • %System Root%\SYSTEM\G-923-321232-3232-32211-23\Desktop.ini

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It drops the following copies of itself into the affected system:

  • %System Root%\SYSTEM\G-923-321232-3232-32211-23\driver.exe

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

Autostart Technique

This backdoor adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{67KLN5J0-4OPM-00WE-AAX5-74CC3A182132}
StubPath = "%System Root%\SYSTEM\G-923-321232-3232-32211-23\driver.exe"

Other System Modifications

This backdoor adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{67KLN5J0-4OPM-00WE-AAX5-74CC3A182132}

Other Details

This backdoor connects to the following possibly malicious URL:

  • {BLOCKED}8.{BLOCKED}rk.biz
  • {BLOCKED}8.{BLOCKED}atsccont.biz
  • {BLOCKED}8.{BLOCKED}ils.net

  SOLUTION

Minimum Scan Engine: 9.200
FIRST VSAPI PATTERN FILE: 6.766.05
FIRST VSAPI PATTERN DATE: 13 Jan 2010
VSAPI OPR PATTERN File: 6.767.00
VSAPI OPR PATTERN Date: 14 Jan 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

Restart in Safe Mode

[ Learn More ]

Step 3

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components
    • {67KLN5J0-4OPM-00WE-AAX5-74CC3A182132}

Step 4

Search and delete these files

[ Learn More ]
There may be some component 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.
  • %System Root%\SYSTEM\G-923-321232-3232-32211-23\Desktop.ini

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_POISON.AGH. 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.


Did this description help? Tell us how we did.