Threat Descriptions

Backdoor:W32/IRCBot.ET

Classification

Category :

Malware

Type :

Backdoor

Platform :

W32

Aliases :

Backdoor.Win32.IRCBot.et

Summary

A remote administration tool (RAT) that bypasses the security features of a program, computer or network to give unauthorized access or control to its user.

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

Backdoor:W32/IRCBot.ET is a variant of a bot that spreads by exploiting the known Plug and Play service (MS05-039) vulnerability. It is a packed PE executable file 51326 bytes long.

The bot was first found on August, 16th 2005.

Installation

When run, the worm copies under %SYSTEM% directory using the name 'windrg32.exe'. Then it adds the following registry entries to ensure that it is started when a user logs on or the system is restarted:

  • [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run] "winDrg32" = "windrg32.exe"

Propagation

The worm scans for systems vulnerable to Microsoft Windows Plug and Play service (MS05-039) through TCP/445. Please see the following page for detailed information on the vulnerability: http://www.microsoft.com/technet/security/Bulletin/MS05-039.mspx

The following ports are used in attack:

  • Port 445:The worm scans for systems vulnerable to PnP exploit through this port
  • Port 29463: FTP server port on infected systems
  • Port 6667:The command shell port opened by the exploit code.

Activity

The worm tries to connect to IRC channel at predefined address. The attacker who knows channel password can instruct the bot to execute the following actions:

  • Disconnect/reconnect from the IRC channel
  • Request system information
  • Download and execute files
  • Remove worm from the system
  • Manipulate system security settings

IRCBot.ET also tries to uninstall some other malware and adware by deleting files and folders and removing registry keys. The worm tries to terminates the following processes:

  • botzor.exe (Net-Worm.Win32.Mytob.cd / Zotob.A)
  • CMESys.ex
  • csm.exe (Net-Worm.Win32.Mytob.cf / Zotob.B)
  • CxtPls.exe
  • NHUpdater.exe
  • pnpsrv.exe (Backdoor.Win32.Rbot.yk
  • qttask.exe
  • realsched.exe
  • ViewMgr.exe
  • winpnp.exe (Backdoor.Win32.Rbot.ym)

File System Changes

Removes these files:

  • %ProgramFiles%\180Solutions
  • %ProgramFiles%\180Solutions\*.exe
  • %ProgramFiles%\AutoUpdate
  • %ProgramFiles%\AutoUpdate\AutoUpdate.exe
  • %ProgramFiles%\Common Files\CMEII
  • %ProgramFiles%\Common Files\GMT
  • %ProgramFiles%\Common Files\GMT\GMT.exe
  • %ProgramFiles%\Common Files\WinTools
  • %ProgramFiles%\Common Files\WinTools\*.exe
  • %ProgramFiles%\CxtPls
  • %ProgramFiles%\EbatesMoeMoneyMaker
  • %ProgramFiles%\eZula
  • %ProgramFiles%\eZula\mmod.exe
  • %ProgramFiles%\Hotbar
  • %ProgramFiles%\Hotbar\*.exe
  • %ProgramFiles%\MyWay
  • %ProgramFiles%\MyWay\*.exe
  • %ProgramFiles%\MyWebSearch
  • %ProgramFiles%\MyWebSearch\*.exe
  • %ProgramFiles%\NavExcel
  • %ProgramFiles%\Toolbar
  • %ProgramFiles%\Toolbar\*.exe
  • %System%\botzor.exe
  • %System%\csm.exe
  • %System%\pnpsrv.exe
  • %System%\winpnp.exe

Registry Modifications

Deletes these values:

  • [HKCU\Software\Microsoft\Windows\Run] "180" "180ax" "Apropos" "AutoUpdater" "CMESys" "csm Win Updates" "Ebates" "EbatesMoeMoneyMaker" "eZmmod" "eZula" "Gator" "GatorDownloader" "Hotbar" "IBIS TB" "lgbibsn" "msbb" "MyWay" "MyWebSearch" "NavExcel" "QuickTime" "QuickTime Task" "Real" "saie" "sais" "TBPS" "TkBellExe" "Toolbar" "tov" "Trickler" "ViewMgr" "Viewpoint" "WeatherOnTray" "Windows PNP" "Windows PNP Server" "WINDOWS SYSTEM" "WinTools" "Zotob"