Analysis by: Jeffrey Francis Bonaobra
ALIASES:

Trojan:Win32/Lockbit.HA!MTB (MICROSOFT)

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size: 162,816 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 01 Sep 2022

Arrival Details

This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Ransomware drops the following files:

  • {Encrypted directory}\GPfGYbfQG.README.txt
  • %ProgramData%\GPfGYbfQG.ico
  • %ProgramData%\GPfGYbfQG.bmp

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.)

Other System Modifications

This Ransomware adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
.GPfGYbfQG
(Default) = GPfGYbfQG

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
GPfGYbfQG\DefaultIcon
(Default) = %ProgramData%\GPfGYbfQG.ico

It changes the desktop wallpaper by modifying the following registry entries:

HKEY_CURRENT_USER\ControlPanel\Desktop
Wallpaper = %ProgramData%\GPfGYbfQG.bmp

Other Details

This Ransomware adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
GPfGYbfQG

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
.GPfGYbfQG

Ransomware Routine

This Ransomware renames encrypted files using the following names:

  • {random characters}.GPfGYbfQG

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 17.730.08
FIRST VSAPI PATTERN DATE: 05 Aug 2022
VSAPI OPR PATTERN File: 17.731.00
VSAPI OPR PATTERN Date: 06 Aug 2022

Step 1

Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:

     
    • Troj.Win32.TRX.XXPE50FFF060

Step 2

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 3

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 4

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\Classes\.GPfGYbfQG
    • (Default) = GPfGYbfQG
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\GPfGYbfQG\DefaultIcon
    • (Default) = %ProgramData%\GPfGYbfQG.ico
  • In HKEY_CURRENT_USER\ControlPanel\Desktop
    • Wallpaper = %ProgramData%\GPfGYbfQG.bmp

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_LOCAL_MACHINE\SOFTWARE\Classes
    • .GPfGYbfQG
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes
    • GPfGYbfQG

Step 6

Search and delete this file

[ Learn More ]
There may be some 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.
  • {Encrypted directory}\GPfGYbfQG.README.txt
  • %ProgramData%\GPfGYbfQG.ico
  • %ProgramData%\GPfGYbfQG.bmp

Step 7

Reset your Desktop properties

[ Learn More ]

Step 8

Scan your computer with your Trend Micro product to delete files detected as Ransom.Win32.LOCKBIT.SMYXCGU. 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 the following Trend Micro Support pages for more information:


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