BKDR_REFPRON.EB

October 03, 2012
 ALIASES:

Virus:Win32/Virut.L (Microsoft); W32/Virut.gen (McAfee); W32.Virut.U (Symantec); Trojan-Downloader.Win32.Delf.ugt (Kaspersky); Backdoor.Win32.Refpron.at (v) (Sunbelt); Backdoor:W32/Refpron.gen!E (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This backdoor 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:

168,960 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

03 Oct 2012

Arrival Details

This backdoor 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 backdoor modifies the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Session Manager\SFC
ProgramFilesDir = "%Program Files%"

(Note: The default value data of the said registry entry is %Program Files%.)

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\Session Manager\SFC
CommonFilesDir = "%Program Files%\Common Files"

(Note: The default value data of the said registry entry is %Program Files%\Common Files.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.200

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

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_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Session Manager\SFC
    • From: ProgramFilesDir = "%Program Files%"
      To: ProgramFilesDir = ""%Program Files%""
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Session Manager\SFC
    • From: CommonFilesDir = "%Program Files%\Common Files"
      To: CommonFilesDir = ""%Program Files%\Common Files""

Step 3

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