Analysis by: Jaime Benigno Reyes
 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • 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: 114,176 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 25 Apr 2014

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 drops the following files:

  • %User Temp%\{random folder name 1}\{random folder name 2}\wow.dll
  • %User Temp%\{random folder name 1}\{random folder name 2}\wow.ini

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

It creates the following folders:

  • %User Temp%\{random folder name 1}
  • %User Temp%\{random folder name 1}\{random folder name 2}

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

Other System Modifications

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

KEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\EFS\
CurrentKeys
numbackupattempts = "4294967295"

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}c.com:81
  • http://{BLOCKED}5.com:81
  • http://{BLOCKED}.{BLOCKED}.192.215:81
  • http://{BLOCKED}.{BLOCKED}.174.45:81

  SOLUTION

Minimum Scan Engine: 9.700

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

Restart in Safe Mode

[ Learn More ]

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.  
  • %User Temp%\{random folder name 1}
  • %User Temp%\{random folder name 1}\{random folder name 2}

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 KEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\EFS\CurrentKeys
    • numbackupattempts = "4294967295"


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