BKDR_SHOTODOR.D

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.

It executes commands from a remote malicious user, effectively compromising the affected system.

It modifies the Internet Explorer Zone Settings.

It logs a user's keystrokes to steal information.

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.

Installation

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

• %Application Data%\mOVR48rQ\AmjcyuV.exe

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

It creates the following folders:

• %User Profile%\mOVR48rQ
• %Application Data%\dclogs

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

It adds the following mutexes to ensure that only one of its copies runs at any one time:

• DC_MUTEX-TS2BJ2B

It stays memory-resident by injecting codes into the following processes:

• %Windows%\Microsoft.NET\Framework\v2.0.50727\cvtres.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

Autostart Technique

This backdoor adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
IsXpDUyTCH = "%Application Data%\mOVR48rQ\AmjcyuV.lnk"

It drops the following shortcut pointing to its copy in the User Startup folder to enable its automatic execution at every system startup:

• %Application Data%\mOVR48rQ\AmjcyuV.lnk (Autorun Registry)

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

Other System Modifications

This backdoor adds the following registry keys:

HKEY_CURRENT_USER\Software\DC3_FEXEC

Backdoor Routine

This backdoor executes the following commands from a remote malicious user:

• Capture video from webcam
• Change MSN Messenger & MSN contact list status
• Empty Recycle Bin
• List active windows
• Remote shell command
• Download and execute files
• Download updated copy of itself
• Upload files
• Log keystrokes
• Modify system's host file
• Record sounds
• Open and close CD-ROM drive door
• Steal passwords
• Get torrent files
• Refresh Wifi
• Uninstall programs
• Manipulate the following:
  • Browser
  • Clipboard
  • Desktop
  • Dialog Box
  • Files
  • Folders
  • Mouse clicks
  • Processes
  • Registries
  • Services
  • Shutdown button options
  • Start button
  • System clock
  • System tray
  • Taskbar

It connects to the following URL(s) to send and receive commands from a remote malicious user:

• {BLOCKED}a.{BLOCKED}p.org:1112

Web Browser Home Page and Search Page Modification

This backdoor modifies the Internet Explorer Zone Settings.

Information Theft

This backdoor gathers the following data:

• Admin rights
• Computer/User name
• Language/Country
• Operating System information

It logs a user's keystrokes to steal information.

Stolen Information

The stolen information is saved in the following file:

• %Application Data%\dclogs\{Current Date}-{Number}.dc

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