Analysis by: Marfel Tiamzon
 PLATFORM:

Windows 98, ME, NT, 2000, XP, Server 2003

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This worm 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. It disables Task Manager, Registry Editor, and Folder Options.

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

  TECHNICAL DETAILS

File Size: 1,367,248 bytes
Memory Resident: Yes

Installation

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

  • %WINDOWS%\Sgt.sys.vbs

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
SysCom = %WINDOWS%\Sgt.sys.vbs

Other System Modifications

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

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
VBSFile
DefaultIcon = shell32.dll,5

HKEY_CLASSES_ROOT\VBSFile
DefaultIcon = shell32.dll,5

HKEY_CURRENT_USER\Softeware\Microsoft\
Internet Explorer\Main
Window Title = Bertakwalah kepada Alloh dimanapun kau berada.

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
=

It adds the following registry entries to disable the Task Manager:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
DisableTaskMgr = 0

It creates the following registry entry(ies) to disable Task Manager, Registry Tools and Folder Options:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer
NoFolderOptions = 0
NoFind = 0
NoRun = 0
NoFileAssociate = 0
DisableRegedit = 0
DisableCMD = 0

Propagation

This worm drops the following copies of itself in all physical and removable drives:

  • Sgt.sys.vbs

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

The said .INF file contains the following strings:

[autorun]
shellexecute=wscript.exe Sgt.sys.vbs

  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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • SysCom = %Windows%\Sgt.sys.vbs
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\VBSFile
    • DefaultIcon = shell32.dll,5
  • In HKEY_CLASSES_ROOT\VBSFile
    • DefaultIcon = shell32.dll,5
  • In HKEY_CURRENT_USER\Softeware\Microsoft\Internet Explorer\Main
    • Window Title = Bertakwalah kepada Alloh dimanapun kau berada.

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies
    • System

Step 4

Scan your computer with your Trend Micro product to delete files detected as VBS_AUTORUN.FKJ. 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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