Analysis by: Roland Marco Dela Paz
 Modified by: Christopher Daniel So
ALIASES:

Troj/Lineag-GQ (Sophos); Trojan-GameThief.Win32.Magania.cdzz (Kaspersky)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

This Trojan injects itself into Internet Explorer when executed. It also connects to a website in an attempt to possibly download files that may be malicious onto the infected system.

  TECHNICAL DETAILS

File Size: 74,946 bytes
File Type: PE
Memory Resident: No
Initial Samples Received Date: 04 Feb 2011

Installation

This Trojan drops the following non-malicious file:

  • %Current%\Cexe

It injects codes into the following process(es):

  • iexplore.exe

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CLASSES_ROOT\CLSID\MADOWN

It modifies the following registry entries:

HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Explorer\
Advanced
Hidden = 2

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Explorer\
Advanced
ShowSuperHidden = 0

(Note: The default value data of the said registry entry is 1.)

HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Explorer\
Advanced\Folder\Hidden\
SHOWALL
CheckedValue = 0

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Policies\
Explorer
NoDriveTypeAutoRun = 91

(Note: The default value data of the said registry entry is 95.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}a.com/1rb/ar1.rar

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.812.05
FIRST VSAPI PATTERN DATE: 04 Feb 2011
VSAPI OPR PATTERN File: 7.813.00
VSAPI OPR PATTERN Date: 04 Feb 2011

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_CLASSES_ROOT\CLSID
    • MADOWN

Step 4

Restore this modified 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\Explorer\Advanced
    • From: Hidden = 2
      To: Hidden = 1
  • In HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\Windows\CURRENTVERSION\Explorer\Advanced
    • From: ShowSuperHidden = 0
      To: ShowSuperHidden = 1
  • In HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\Windows\CURRENTVERSION\Explorer\Advanced\Folder\Hidden\SHOWALL
    • From: CheckedValue = 0
      To: CheckedValue = 1
  • In HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\Windows\CURRENTVERSION\Policies\Explorer
    • From: NoDriveTypeAutoRun = 91
      To: NoDriveTypeAutoRun = 95

Step 5

Search and delete this file

[ 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. Cexe

Step 6

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