BKDR_PLUGX.AZA

September 07, 2013
 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:

311,296 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

07 Sep 2013

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 creates the following folders:

  • %User Profile%\SxS

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

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
GraphCmd Server = "{malware path and file name}"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
GraphCmd Server = "{malware path and file name}"

Other System Modifications

This backdoor adds the following registry keys:

HKEY_LOCAL_MACHINE\Software\CLASSES\
MJ

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
5.0\User Agent\Post Platform

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\Internet Settings\
User Agent\Post Platform

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
MJ
CLSID = "{random values}"

Other Details

This backdoor connects to the following possibly malicious URL:

  • http://im.{BLOCKED}n2010.info/update?id=000fa7a8
  • http://im.{BLOCKED}n2010.info/update?id=000fa8c0

This report is generated via an automated analysis system.

  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

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\CLASSES
    • MJ
  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\5.0\User Agent
    • Post Platform
  • In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\User Agent
    • Post Platform

Step 4

Delete this registry value

[ 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\Windows\CurrentVersion\Run
    • GraphCmd Server = "{malware path and file name}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • GraphCmd Server = "{malware path and file name}"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\MJ
    • CLSID = "{random values}"

Step 5

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Profile%\SxS

Step 6

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