TROJ_RANSOM.CQ

 Analysis by: Roland Marco Dela Paz

 PLATFORM:

Windows 2000, XP, 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 may be unknowingly downloaded by a user while visiting malicious websites. It may be manually installed by a user.

It adds certain registry entries to disable the Task Manager. This action prevents users from terminating the malware process, which can usually be done via the Task Manager.

  TECHNICAL DETAILS

File Size:

169,472 bytes

File Type:

PE

Memory Resident:

Yes

Initial Samples Received Date:

10 Sep 2010

Payload:

Displays graphics/image

Arrival Details

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

It may be manually installed by a user.

Autostart Technique

This Trojan modifies the following registry entry(ies) to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\
WINDOWS NT\CURRENTVERSION\Winlogon
Shell = {malware path and file name}

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

Other System Modifications

This Trojan adds the following registry entries to disable the Task Manager:

HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\
Windows\CURRENTVERSION\Policies\
SYSTEM
DisableTaskMgr = 1

Other Details

This Trojan displays the following images:

It does the following:

  • Once executed, it displays a specific window and prevents any software from execution.
  • It then asks for a valid serial number in order to unlock Windows.
  • NOTE: User may use the following code to deactivate the malware: #5020543#

  SOLUTION

Minimum Scan Engine:

8.900

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

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\Policies\SYSTEM
    • DisableTaskMgr = 1

Step 3

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_LOCAL_MACHINE\SOFTWARE\MICROSOFT\WINDOWS NT\CURRENTVERSION\Winlogon
    • From: Shell = {malware path and file name}
      To: Shell = Explorer.exe
      • From:      

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_RANSOM.CQ. 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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