Modified by: Christopher Daniel So
ALIASES:

Worm:Win32/Taterf.B (Microsoft), W32/Lineage.LLI (Panda), TrojanPSW.Magania.dqom (VBA32)

 PLATFORM:

Windows 2000, XP, Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

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

  TECHNICAL DETAILS

File Size: 171,520 bytes
File Type: PE
File Compression: Aspack
Memory Resident: Yes
Initial Samples Received Date: 30 Nov 2010
Payload: Drops files, Downloads files

Arrival Details

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

It may be dropped by other malware.

Installation

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

  • %User Temp%\xvassdf.exe

(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.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
54dfsger = "%User Temp%\xvassdf.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
king_jp = "%System%\jpking.exe"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CLASSES_ROOT\CLSID\MADOWN

It adds the following registry entries as part of its installation routine:

HKEY_CLASSES_ROOT\CLSID\MADOWN
urlinfo = "twgtj.f"

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\ar.exe
  • %User Temp%\ar1.rar

(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.)

It drops the following files:

  • %System%\jpking.exe - detected as Mal_OLGM-41
  • %System%\jpking0.dll - detected as Mal_OLGM-41
  • %User Temp%\4tddfwq0.dll - detected as TROJ_BTGF.A

(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.. %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.)

Download Routine

This Trojan connects to the following URL(s) to download its component file(s):

  • http://www.{BLOCKED}sw.com/1rb/ar1.rar
  • http://www.{BLOCKED}k4.com/1rb/ar.rar
  • http://www.{BLOCKED}k4.com/1rb/ar1.rar

  SOLUTION

Minimum Scan Engine: 8.900
VSAPI PATTERN File: 7.662.06
VSAPI PATTERN Date: 30 Nov 2010
VSAPI PATTERN Date: 11/30/2010 12:00:00 AM

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

Remove malware files dropped/downloaded by TROJ_DROPPER.OKQ

    TROJ_BTGF.A

Step 3

Restart in Safe Mode

[ Learn More ]

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%\jpking.exe
%System%\jpking0.dll
%User Temp%\4tddfwq0.dll
%User Temp%\ar.exe
%User Temp%\ar1.rar

Step 5

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_CLASSES_ROOT\CLSID
    • MADOWN

Step 6

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • 54dfsger=%User Temp%\xvassdf.exe
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • king_jp=%System%\jpking.exe

Step 7

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