Analysis by: Francesca Villasanta

ALIASES:

HEUR:Trojan.Script.Generic (KASPERSKY); TrojanDownloader:O97M/Emotet.SS!MTB (MICROSOFT)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, Dropped by other malware

This Trojan 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: 527220736 bytes
File Type: DOC
Memory Resident: No
Initial Samples Received Date: 09 Mar 2023
Payload: Displays message/message boxes, Connects to URLs/IPs, Downloads files, Modifies system registry

Arrival Details

This Trojan 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 Trojan adds the following folders:

  • {Malware Path}\{Random Numbers} → deleted afterwards

It drops the following files:

  • {Malware Path}\{Random Numbers}\fVyjQAytyWVqgIJ.dll
  • {Malware Path}\{Random Numbers}.tmp → renamed and moved copy of fVyjQAytyWVqgIJ.dll
  • {Malware Path}\{Random Numbers}.zip → deleted afterwards

It adds the following processes:

  • "%System%\regsvr32.exe" /s "{Malware Path}\{Random Numbers}.tmp"

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Other System Modifications

This Trojan adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Discardable\PostSetup\Component Categories\
{56FFCC30-D398-11D0-B2AE-00A0C908FA49}\Enum
Implementing = {Hex Values}

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Shell Extensions\
Cached
{2781761E-28E0-4109-99FE-B9D127C57AFE} {56FFCC30-D398-11D0-B2AE-00A0C908FA49} 0xFFFF = {Hex Values}

HKEY_CURRENT_USER\Software\Microsoft\
Office\12.0\Common
QMSessionCount = 2

Other Details

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
VBA

HKEY_CURRENT_USER\Software\Microsoft\
VBA\6.0

HKEY_CURRENT_USER\Software\Microsoft\
VBA\6.0\Common

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Discardable\PostSetup\Component Categories

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Discardable\PostSetup\Component Categories\
{56FFCC30-D398-11D0-B2AE-00A0C908FA49}\Enum

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Discardable\PostSetup\Component Categories\
{56FFCC30-D398-11D0-B2AE-00A0C908FA49}

It connects to the following possibly malicious URL:

  • e{BLOCKED}i-gourmet.kz
  • {BLOCKED}stsupplies.com.au
  • {BLOCKED}isbane.org.au
  • http://a{BLOCKED}un.cn/8uhjvgd/nhAOl4DRmdOKz/?161846&c=1

  SOLUTION

Minimum Scan Engine: 9.800

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

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\Explorer\Discardable\PostSetup\Component Categories\{56FFCC30-D398-11D0-B2AE-00A0C908FA49}\Enum
    • Implementing = {Hex Values}
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Shell Extensions\Cached
    • {2781761E-28E0-4109-99FE-B9D127C57AFE} {56FFCC30-D398-11D0-B2AE-00A0C908FA49} 0xFFFF = {Hex Values}
  • In HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Common
    • QMSessionCount = 2

Step 4

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\VBA
  • In HKEY_CURRENT_USER\Software\Microsoft\VBA\6.0
  • In HKEY_CURRENT_USER\Software\Microsoft\VBA\6.0\Common
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Discardable\PostSetup\Component Categories
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Discardable\PostSetup\Component Categories\{56FFCC30-D398-11D0-B2AE-00A0C908FA49}
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Discardable\PostSetup\Component Categories\{56FFCC30-D398-11D0-B2AE-00A0C908FA49}\Enum

Step 5

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.
  • {Malware Path}\{Random Numbers}.zip
  • {Malware Path}\{Random Numbers}\fVyjQAytyWVqgIJ.dll
  • {Malware Path}\{Random Numbers}.tmp

Step 6

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • {Malware Path}\{Random Numbers}

Step 7

Scan your computer with your Trend Micro product to delete files detected as Trojan.W97M.EMOTET.SPSC. 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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