VBS_PENEPE.SMX

October 12, 2012
 ALIASES:

Backdoor:Win32/Penepe.B, Backdoor:Win32/Penepe.A, Backdoor:Win32/Penepe.A!lnk (Microsoft); Generic BackDoor!ik (McAfee); Trojan Horse (Symantec); PAK:UPX, ARC:ZIP, PAK:[System.exe]:UPX, PAK:[cssrs.exe]:UPX (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.3284044 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 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.

  TECHNICAL DETAILS

File Size:

244,010 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

29 Nov 2011

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 creates the following folders:

  • Data.Msi

Other System Modifications

This Trojan modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
Name = "iexplore.exe"

(Note: The default value data of the said registry entry is mshta.exe.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
DirectDraw\MostRecentApplication
ID = 4117b81

(Note: The default value data of the said registry entry is 41107b3f.)

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\sfx.ini
  • startup.vbe
  • System.exe
  • alg.vbe
  • cssrs.exe
  • DiskDoctor.lnk
  • pic.url
  • %Application Data%\PUTTY.RND
  • %User Startup%\DiskDoctor.lnk

(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.. %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.. %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)

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\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
    • From: Name="iexplore.exe"
      To: Name=mshta.exe
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\DirectDraw\MostRecentApplication
    • From: ID=4117b81
      To: ID=41107b3f

Step 3

Search and delete this folder

[ 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. Data.Msi

Step 4

Search and delete these files

[ Learn More ]
There may be some component 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.
  • %User Temp%\sfx.ini
  • startup.vbe
  • System.exe
  • alg.vbe
  • cssrs.exe
  • DiskDoctor.lnk
  • pic.url
  • %Application Data%\PUTTY.RND
  • %User Startup%\DiskDoctor.lnk

Step 5

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


Did this description help? Tell us how we did.