arrow_back
search
close

VBS_DUNIHI.YYSWJ

May 14, 2018
 Analysis by: John Kevin Sanchez
 ALIASES:

VBS.Dunihi (Symantec), VBS/Autorun.worm.aafs (McAfee)

 PLATFORM:

Windows

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Worm 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:

187,866 bytes

File Type:

VBS

Memory Resident:

Yes

Initial Samples Received Date:

11 May 2018

Arrival Details

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

  • %Application Data%\Adobe PhotoShop\Pictur.Png
  • %Application Data%\Adobe PhotoShop\Public\XNXX\Pictur.Png
  • %Application Data%\Adobe PhotoShop\Public\MUSIC\Pictur.Png
  • %Application Data%\Adobe PhotoShop\Public\DCIM\Pictur.Png
  • %Application Data%\Adobe PhotoShop\Public\MOVIES\Pictur.Png
  • %Application Data%\Adobe PhotoShop\Public\VIDEO\Pictur.Png
  • {Removable Drive}\Adobe\Pictur.Png

(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.)

It drops the following files:

  • %Application Data%\Adobe PhotoShop\Startrun.pif
  • %Application Data%\Adobe PhotoShop\runsc.exe
  • %Application Data%\Adobe PhotoShop\Public\XNXX\Video.Mp4.lnk
  • %Application Data%\Adobe PhotoShop\Public\MUSIC\Music.Mp3.lnk
  • %Application Data%\Adobe PhotoShop\Public\DCIM\Pictur.jpg.lnk
  • %Application Data%\Adobe PhotoShop\Public\MOVIES\Movies.Mp4.lnk
  • %Application Data%\Adobe PhotoShop\Public\VIDEO\YouTube.Flv.lnk
  • {Removable Drive}\DCIM.lnk

(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.)

It creates the following folders:

  • %Application Data%\Adobe PhotoShop
  • %Application Data%\Adobe PhotoShop\Public
  • %Application Data%\Adobe PhotoShop\Public\XNXX
  • %Application Data%\Adobe PhotoShop\Public\MUSIC
  • %Application Data%\Adobe PhotoShop\Public\DCIM
  • %Application Data%\Adobe PhotoShop\Public\MOVIES
  • %Application Data%\Adobe PhotoShop\Public\VIDEO
  • {Removable Drive}\Adobe

(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.)

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
Adobe PhotoShop = "%Application Data%\Adobe PhotoShop\Startrun.pif" /E:Vbscript.Encode "%Application Data%\Adobe PhotoShop\Pictur.Png

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
Adobe PhotoShop = "%Application Data%\Adobe PhotoShop\Startrun.pif" /E:Vbscript.Encode "%Application Data%\Adobe PhotoShop\Pictur.Png

Other System Modifications

This Worm adds the following registry entries:

HKEY_CURRENT_USER\Software
Adobe PhotoShop = {True or False} - {Date of Infection}

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = 0

(Note: The default value data of the said registry entry is 1.)

Propagation

This Worm creates shortcut files (.LNK) disguised as folders or files located on the affected drives pointing to the malware copy.

Other Details

This Worm connects to the following possibly malicious URL:

  • http://mr-wolf.{BLOCKED}me.net:2016/arasramo
  • http://mr-wolf.{BLOCKED}c.net:2016/arasramo
  • http://mr-wolf.{BLOCKED}e.com:2016/arasramo

NOTES:

It deletes the following registry value:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\lnkfile
value: isShorTcut