ALIASES:

TrojanDownloader:Win32/Ruckguv.A (Microsoft); BackDoor-FCNO!331BEC58CB11 (McAfee); Downloader (Symantec); Trojan-Spy.Win32.BitWall.he (Kaspersky); Troj/Agent-AMRV (Sophos); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse Inject2.BZFK (AVG)

 PLATFORM:

Windows

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

  • 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.

It deletes itself after execution.

  TECHNICAL DETAILS

File Size: 114,526 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 12 May 2015

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 deletes the following files:

  • %User Profile%\Application Data\csrss_10.exe
  • %User Profile%\Application Data\Frifox_7.exe
  • %User Profile%\Application Data\WindowsDriver_51.exe

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

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion
path = "{malware path and file name}"

Other Details

This Trojan connects to the following possibly malicious URL:

  • {BLOCKED}0.1

It deletes itself after execution.

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.750

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
    • path = "{malware path and file name}"

Step 3

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

Step 4

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Profile%\Application Data\csrss_10.exe
  • %User Profile%\Application Data\Frifox_7.exe
  • %User Profile%\Application Data\WindowsDriver_51.exe


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