Worm.VBS.SLOZILLA.A

 Analysis by: Mohammed Malubay

 ALIASES:

Worm.VBS.Solow.b(KASPERSKY); Worm:VBS/Slogod.E(MICROSOFT); Worm.VBS.Solow(IKARUS);

 PLATFORM:

Windows

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


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

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:

3,754 bytes

File Type:

VBS

Memory Resident:

Yes

Initial Samples Received Date:

10 Jun 2019

Arrival Details

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

  • %Windows%\MS32DLL.dll.vbs

(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)

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
MS32DLL = "%Windows%\MS32DLL.dll.vbs"

Other System Modifications

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

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Window Title = "Hacked by Godzilla"

Propagation

This Worm drops the following copy of itself in all physical and removable drives:

  • MS32DLL.dll.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 MS32DLL.dll.vbs

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

15.582.04

FIRST VSAPI PATTERN DATE:

26 Dec 2019

VSAPI OPR PATTERN File:

15.583.00

VSAPI OPR PATTERN Date:

27 Dec 2019

Step 1

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 2

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 3

Restart in Safe Mode

[ Learn More ]

Step 4

Search and delete these files

[ 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.
  • %Windows%\MS32DLL.dll.vbs
  • {Removable\Physical Drive}:\MS32DLL.dll.vbs

Step 5

Search and delete AUTORUN.INF files created by Worm.VBS.SLOZILLA.A that contain these strings

[ Learn More ]
  • shellexecute=wscript.exe MS32DLL.dll.vbs

Step 6

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
    • MS32DLL = "%Windows%\MS32DLL.dll.vbs"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • Window Title = "Hacked by Godzilla"

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as Worm.VBS.SLOZILLA.A. 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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