TROJ_VBKRYPT.AQ

 Analysis by: Erika Bianca Mendoza

 PLATFORM:

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

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  TECHNICAL DETAILS

File Size:

65 bytes

File Type:

EXE

Memory Resident:

Yes

Installation

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

  • %Application Data%\SystemProc\lsass.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)

It drops the following files:

  • %Program Files%\Mozilla Firefox\extensions\{8CE11043-9A15-4207-A565-0C94C42D590D}\chrome\content\timer.xul
  • %Program Files%\Mozilla Firefox\extensions\{8CE11043-9A15-4207-A565-0C94C42D590D}\install.rdf
  • %Program Files%\Mozilla Firefox\extensions\{8CE11043-9A15-4207-A565-0C94C42D590D}\chrome.manifest

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files.)

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
Explorer\Run
RTHDBPL = %Application Data%\SystemProc\lsass.exe

Other Details

This Trojan connects to the following possibly malicious URL:

  • gewebsearch.com

  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

Restart in Safe Mode

[ Learn More ]

Step 3

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.

RESTORE
  • Close Registry Editor.
  • 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. DATA_GENERIC
    Note: To do a search for the following files, right-click Start then click Search... or Find..., depending on the version of Windows you are running. For each file to be deleted, type its file name in the Named input box. In the Look In drop-down list, select My Computer, then press Enter.
  • Once located, select the file then press SHIFT+DELETE to permanently delete the file.
  • Repeat the said steps for all files listed.
  • Step 5

    Scan your computer with your Trend Micro product to delete files detected as TROJ_VBKRYPT.AQ. 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.