Analysis by: Cris Nowell Pantanilla
 PLATFORM:

Windows

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Via physical/removable drives

This worm arrives via removable drives.

It drops copies of itself into all the removable drives connected to an affected system.

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size: 177,911 bytes
File Type: VBS
Memory Resident: Yes
Initial Samples Received Date: 30 Mar 2015
Payload: Connects to URLs/IPs

Arrival Details

This worm arrives via removable drives.

Installation

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

  • %Application Data%\Microsoft Office\Microsoft Excel.WsF
  • %User Temp%\Microsoft Office\Microsoft Excel.WsF (if "Application Data" folder does not exist)

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It creates the following folders:

  • %Application Data%\Microsoft Office
  • %User Temp%\Microsoft Office (if "Application Data" folder does not exist)

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Microsoft Excel = "wscript.exe //B "%Application Data%\Microsoft Office\Microsoft Excel.WsF""

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Microsoft Excel = "wscript.exe //B "%Application Data%\Microsoft Office\Microsoft Excel.WsF""

Other System Modifications

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft Excel
(Default) = "FaLsE - {current date}"

Propagation

This worm drops copies of itself into all the removable drives connected to an affected system.

Other Details

This worm connects to the following website to send and receive information:

  • maroco.{BLOCKED}c.net:855
  • maroco.{BLOCKED}e.com:855
  • maroco.{BLOCKED}tme.net:855

NOTES:

This worm is capable of executing the following commands:

  • excecute
  • recv
  • send
  • site-send
  • sleep
  • uninstall
  • update

It searches for anti-malware products installed in the system and reports the information to a remote site.

It searches for removable drives connected to the system. Once found, it searches for files in all folders. It then creates a shortcut link using the file name and point to the copy of the malware in the removable drives. It also sets the attributes of the original files to hidden.

  SOLUTION

Minimum Scan Engine: 9.750
FIRST VSAPI PATTERN FILE: 11.602.04
FIRST VSAPI PATTERN DATE: 30 Mar 2015
VSAPI OPR PATTERN File: 11.603.00
VSAPI OPR PATTERN Date: 31 Mar 2015

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\Windows\CurrentVersion\Run
    • Microsoft Excel = "wscript.exe //B "%Application Data%\Microsoft Office\\Microsoft Excel.WsF""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • Microsoft Excel = "wscript.exe //B "%Application Data%\Microsoft Office\\Microsoft Excel.WsF""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft Excel
    • (Default) = "FaLsE - {current date}"

Step 3

Search and delete these folders

[ 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.
%Application Data%\Microsoft Office
%User Temp%\Microsoft Office (if "Application Data" folder does not exist)

Step 4

Scan your computer with your Trend Micro product to delete files detected as VBS_INJECT.D. 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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