Name :	Backdoor:W32/SubSeven
Detection Names :	SubSeven Backdoor.SubSeven
Category:	Malware
Type:	Backdoor
Platform:	W32

A remote administration utility that bypasses normal security mechanisms to secretly control a program, computer or network.

Automatic Disinfection

Allow F-Secure Anti-Virus to disinfect the relevant files.

For more general information on disinfection, please see Removal Instructions.

Backdoor:W32/SubSeven is a backdoor program that allows a remote user to perform a large range of actions on the affected system.

The first samples of this backdoor were not packed, but later some packed versions appeared which were not easy to detect with contemporary anti-virus programs that had no Win32 'Aspack' file compressor unpacking support.

SubSeven backdoor was first discovered in May, 1999. The backdoor is usually distributed under different names via newsgroups and e-mails.


Execution

When run, the backdoor copies itself to the Windows directory with the original name of the file it was run from or as SERVER.EXE, KERNEL16.DL, RUNDLL16.COM, SYSTEMTRAYICON!.EXE or WINDOW.EXE (names are different in different versions of SubSeven).

Then it unpacks a single DLL file to the Windows System directory - WATCHING.DLL (some versions don't do this). After that the backdoor patches Windows Registry so that its main application will be run during every Windows bootup (Run or RunServices keys). Finally, it creates and modifies some other Registry keys. The backdoor can also install itself to the system by modifying either the WIN.INI or the SYSTEM.INI file.

The latest versions of the SubSeven backdoor drop a small starter program (usually WINDOS.EXE) and register it to be run when any EXE file is started in Windows. By doing this the backdoor ensures that its copy is always in the memory. For specific instructions of how to disinfect these versions please see the bottom of the page.

All the recent versions of SubSeven are supplied with a server configuration utility that allows it to customize server part capabilities - installation method, custom startup message, etc. This method was first introduced by the Back Orifice 2000 backdoor and it allows much more flexibility to backdoors.


Activity

If the SubSeven backdoor task is being active in the memory (and invisible in Task Manager), it looks for TCP/IP connections and if they are established it listens to TCP/IP ports for commands from a client part.

Subseven also tries to use ICQ, IRC and different e-mail accounts to notify the author that his victims are online.

SubSeven's initial version had the following 113 capabilities:

  Fun Manager
  ------------------
  1. Open Web Browser to specified location.
  2. Restart Windows.
  3. Reverse Mouse buttons.
  4. Hide Mouse Pointer.
  5. Move Mouse.
  6. Mouse Trail Config.
  7. Set Volume.
  8. Record Sound file from remote mic.
  9. Change Windows Colors / Restore.
  10. Hung up Internet Connection.
  11. Change Time.
  12. Change Date.
  13. Change Screen resolution.
  14. Hide Desktop Icons / Show
  15. Hide Start Button / Show
  16. Hide taskbar / Show
  17. Opne CD-ROM Drive / Close
  18. Beep computer Speaker / Stop
  19. Turn Monitor Off / On
  20. Disable CTRL+ALT+DEL / Enable
  21. Turn on Scroll Lock / Off
  22. Turn on Caps Locl / Off
  23. Turn on Num Lock / Off

  Connection Manager
  -----------------------------
  1. Connect / Disconnect
  2. IP Scanner
  3. IP Address book
  4. Get Computer Name
  5. Get User Name
  6. Get Windows and System Folder Names
  7. Get Computer Company
  8. Get Windows Version
  9. Get Windows Platform
  10. Get Current Resolution
  11. Get DirectX Version
  12. Get Current Bytes per Pixel settings
  13. Get CPU Vendor
  14. Get CPU Speed
  15. Get Hard Drive Size
  16. Get Hard Drive Free Space
  17. Change Server Port
  18. Set Server Password
  19. Update Server
  20. Close Server
  21. Remove Server
  22. ICQ Pager Connection Notify
  23. IRC Connection Notify
  24. E-Mail Connection Notify

  Keyboard Manager
  --------------------------
  1. Enable Key Logger / Disable
  2. Open Key Logger in a remote Window
  3. Clear the Key Logger Windows
  4. Collect Keys pressed while Offline
  5. Open Chat Victim + Controller
  6. Open Chat among all connected

  Controllers
  --------------
  1. Windows Pop-up Message Manager
  2. Disable Keyboard
  3. Send Keys to a remote Window

  Misc. Manager
  --------------------
  1. Full Screen Capture
  2. Continues Thumbnail Capture
  3. Flip Screen
  4. Open FTP Server
  5. Find Files
  6. Capture from Computer Camera
  7. List Recorded Passwords
  8. List Cached Passwords
  9. Clear Password List
  10. Registry Editor
  11. Send Text ot Printer

  File Manager
  ------------------
  1. Show files/folders and navigate
  2. List Drives
  3. Execute Application
  4. Enter Manual Command
  5. Type path Manually
  6. Download files
  7. Upload files
  8. Get File Size
  9. Delete File
  10. Play *.WAV
  11. Set Wallpaper
  12. Print *.TXT\*.RTF file
  13. Show Image

  Window Manager
  ------------------------
  1. List visible windows
  2. List All Active Applications
  3. Focus on Window
  4. Close Window
  5. Disable X (close) button
  6. Hide a Window from view.
  7. Show a Hidden Window
  8. Disable Window
  9. Enable Disabled Window

  Options Menu
  --------------------
  1. Set Quality of Full Screen Capture
  2. Set Quality of Thumbnail Capture
  3. Set Chat font size and Colors
  4. Set Client's User Name
  5. Set local 'Download' Directory
  6. Set Quick Help
  7. Set Client Skin
  8. Set Fun Manager Skin

  Edit Server
  --------------
  1. PreSet Target Port
  2. PreSet server Password
  3. Attach EXE File
  4. PreSet filename after installation
  5. PreSet Registry Key
  6. PreSet Autostart Method:
  Registry: Run
  Registry: RunSevices
  Win.ini
  Less known method
  7. PreSet Fake error message
  8. PreSet Connection Notify Username
  9. PreSet Connection Notify ICQ#
  10. PreSet Connection Notify E-Mail
  11. PreSet Connection Notify IRC Chan.
  12. PreSet IRC Port
  13. Change Server *.exe Icon