ALIASES:

Virus:W97M/Marker.BR (Microsoft), W97M/Marker.ay (McAfee), WM97/Marker-BP (Sophos)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

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: 64,512 bytes
File Type: DOC
Initial Samples Received Date: 24 May 2010

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.

Other System Modifications

This Trojan adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
MS Setup (ACME)\User Info
LogData in = "True"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Desktop\General
Wallpaper = "%System Root%\Jon.html"

It adds the following registry keys as part of its installation routine:

HKEY_CURRENT_USER\Software\Microsoft\
MS Setup (ACME)\User Info

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Office\{version}\Common\
UserInfo
UserName = "JonMMx 2000"

(Note: The default value data of the said registry entry is user-defined.)

HKEY_CURRENT_USER\Software\Microsoft\
Office\{version}\Common\
UserInfo
UserInitials = "MeMex"

(Note: The default value data of the said registry entry is user-defined.)

Dropping Routine

This Trojan drops the following files:

  • %System Root%\Jon.html

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

  SOLUTION

Minimum Scan Engine: 9.700
FIRST VSAPI PATTERN FILE: 7.192.13
FIRST VSAPI PATTERN DATE: 24 May 2010
VSAPI OPR PATTERN File: 7.193.00
VSAPI OPR PATTERN Date: 25 May 2010

Step 1

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

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_CURRENT_USER\Software\Microsoft\Internet Explorer\Desktop\General
    • Wallpaper = "%System Root%\Jon.html"

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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\MS Setup (ACME)
    • User Info

Step 4

Restore this modified 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\Office\{version}\Common\UserInfo
    • From: UserName = "JonMMx 2000"
      To: UserName = "{user-defined}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Office\{version}\Common\UserInfo
    • From: UserInitials = "MeMex"
      To: UserInitials = "{user-defined}"

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.
  • %System Root%\Jon.html

Step 6

Scan your computer with your Trend Micro product to delete files detected as W97M_MARKER.BO. 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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