BKDR_POISON.TM

October 09, 2012
 Analysis by: Lord Alfred Remorin
 ALIASES:

WS.Reputation.1 (Symantec)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Via email, Downloaded from the Internet, Dropped by other malware

This backdoor monitors user activities and records messages posted to the system message queue which may include keystrokes to steal user information such as username and password.

This backdoor arrives as attachment to mass-mailed email messages. It may be dropped by other malware. It may be unknowingly downloaded by a user while visiting malicious websites.

It opens a hidden Internet Explorer window. It connects to a website to send and receive information.

  TECHNICAL DETAILS

File Size:

356,352 bytes

File Type:

PE

Memory Resident:

Yes

Initial Samples Received Date:

08 Aug 2012

Payload:

Steals information

Arrival Details

This backdoor arrives as attachment to mass-mailed email messages.

It may be dropped by other malware.

It may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This backdoor drops the following copies of itself into the affected system:

  • %System%\ViewScript.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

It injects threads into the following normal process(es):

  • EXPLORER.EXE

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
Adobe ViewScript = "%System%\ViewScript.exe"

Backdoor Routine

This backdoor opens a hidden Internet Explorer window.

It connects to the following websites to send and receive information:

  • abcd120807.{BLOCKED}2.org

NOTES:

This backdoor monitors user activities and records messages posted to the system message queue which may include keystrokes to steal user information such as username and password.

  SOLUTION

Minimum Scan Engine:

8.900

FIRST VSAPI PATTERN FILE:

9.312.03

FIRST VSAPI PATTERN DATE:

09 Aug 2012

VSAPI OPR PATTERN File:

9.313.00

VSAPI OPR PATTERN Date:

10 Aug 2012

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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • Adobe ViewScript = "%System%\ViewScript.exe"

Step 4

Scan your computer with your Trend Micro product to delete files detected as BKDR_POISON.TM. 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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