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IRC-Worm:W32/Fagot

Classification

Category: Malware

Type: IRC-Worm

Aliases: IRC-Worm:W32/Fagot

Summary


A standalone malicious program which uses computer or network resources to make complete copies of itself.

Removal


Automatic action

Based on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the detected program or file, or ask you for a desired action.

Knowledge Base

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About the product

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Submit a sample

Submit a file or URL for further analysis.

Technical Details


Fagot is an IRC worm that works by sending messages via IRC chat, trying to get people to click on a web link, which would download "britney.jpg" from www.angelfire.com. The britney.jpg file isn't actually a picture, but a HTML page that contains a script code. When the downloaded HTML page is opened with Internet Explorer, the script is executed. The first part of the script contain Visual Basic Script code that uses an exploit to replace the Windows Media Player with a file ("patch.exe") that is downloaded from another web location. Next the second part (written with JavaScript) of the script is executed, causing the replaced medial player to execute after five seconds. The "patch.exe" file was taken offline already by the time we got reports on this worm on Sunday the 26th of October, therefore the worm doesn't work any more.

History

The first variant which was found in the end of October 2003. The spread of the worm was quickly stopped, as a web file it needed was taken offline.

A new variant of Fagot was discovered November 11th, 2003. This variant uses the link that points to home.amis.net. However, this variant of the worm is also stopped, as the file at the web site was removed.

Execution

The PATCH.EXE file is the worm's component responsible for killing anti-virus and security software tasks and for sending links to the infected HTML file to IRC networks. The file is a Windows PE executable compressed with UPX file compressor. The packed size is 156 kilybytes, the unpacked size is about 382 kilobytes. When the PATCH.EXE file is run, it does the following: * Kills processes with the following names:

  • Ad-watch.exe
  • regedit.exe
  • taskmgr.exe

* Copies the worm's file to Windows System folder with the following name:

  • C:\Windows\system32\userinit32.exe

* Creates a startup key for the copied file in System Registry:

  • [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon] "Userinit" = "C:\Windows\system32\userinit32.exe"

* Copies the worm's file to Windows System folder with the following name:

  • C:\Windows\system32\dllhost32.exe

* Creates a startup key for the copied file in System Registry:

  • [HKLM\Software\Microsoft\Windows\CurrentVersion\Run] "dllhost32" = "C:\Windows\system32\dllhost32.exe"

* Kills the following processes:

  • FSGK32.EXE
  • FSM32.EXE
  • FSMA32.EXE
  • FSMB32.EXE
  • FWENC.EXE
  • KAVLITE40ENG.EXE
  • KAVPERS40ENG.EXE
  • NAV Auto-Protect
  • NAVAPSVC.EXE
  • NMAIN.EXE
  • NORMIST.EXE
  • NORTON_INTERNET_SECU_3.0_407.EXE
  • NPF40_TW_98_NT_ME_2K.EXE
  • NPFMESSENGER.EXE
  • NPROTECT.EXE
  • NPSSVC.EXE
  • NSCHED32.EXE
  • NTVDM.EXE
  • ZAPRO.EXE
  • ZAPSETUP3001.EXE
  • ZATUTOR.EXE
  • ZAUINST.EXE
  • ZONALM2601.EXE
  • ZONEALARM.EXE
  • _AVP32.EXE
  • _AVPCC.EXE
  • _AVPM.EXE
  • ccEvtMgr.exe
  • ccSetMgr.exe
  • FSAV32.exe
  • FSMA32.exe
  • FSMB32.exe
  • FSSM32.exe
  • AVNT.exe
  • AVP.exe
  • BLACKICE.exe
  • FPROT.exe
  • FP-WIN.exe
  • N32SCANW.EXE
  • NAVAPW32.EXE
  • PAVCL.EXE
  • PAVSCHED.EXE
  • WFINDV32.EXE
  • NAVW32.EXE
  • BlackICE.exe

* Changes the startup page of Internet Explorer to:

  • www.blacksnake.com

* Changes default Windows logon names to:

  • COCK_SUCKING_FAGGOT

* Deletes the following files if they are present:

  • C:\windows\regedit.exe
  • C:\windows\cmd.exe
  • C:\windows\system32\taskman.exe
  • C:\windows\system32\taskmgr.exe
  • C:\windows\system32\regedt32.exe
  • C:\windows\system32\regsvr32.exe
  • C:\windows\TASKMAN.exe
  • C:\windows\system32\autochk.exe
  • C:\windows\system32\chkntfs.exe
  • C:\windows\system32\chkdsk.exe
  • C:\windows\system32\shutdown.exe
  • C:\windows\NOTEPAD.exe
  • C:\WINDOWS\system32\userinit.exe
  • C:\windows\system32\progman.exe
  • C:\windows\regedit.exe
  • C:\windows\cmd.exe
  • C:\windows\system32\taskman.exe
  • C:\windows\system32\taskmgr.exe
  • C:\windows\system32\regedt32.exe
  • C:\windows\system32\regsvr32.exe
  • C:\windows\TASKMAN.exe
  • C:\windows\system32\autochk.exe
  • C:\windows\system32\chkntfs.exe
  • C:\windows\system32\chkdsk.exe
  • C:\windows\system32\shutdown.exe
  • C:\windows\NOTEPAD.exe
  • C:\WINDOWS\system32\userinit.exe
  • C:\windows\system32\progman.exe
  • C:\windows\system32\ntoskrnl.exe
  • C:\windows\system32\ntkrnlpa.exe
  • C:\windows\system32\alg.exe
  • C:\windows\system32\bootok.exe
  • C:\windows\system32\chcp.exe
  • C:\windows\system32\ctfmon.exe
  • C:\windows\system32\dumprep.exe
  • C:\windows\system32\recover.exe
  • C:\windows\system32\imapi.exe
  • C:\windows\system32\logon.exe
  • C:\windows\system32\MDM.exe
  • C:\windows\system32\services.exe
  • C:\windows\system32\systray.exe
  • C:\windows\system32\win.exe
  • C:\windows\system32\wowexec.exe
  • C:\windows\system32\wuauclt.exe

* Copies itself with different names:

  • C:\windows\NOTEPAD.exe
  • C:\WINDOWS\system32\userinit.exe
  • C:\windows\system32\progman.exe
  • C:\windows\regedit.exe
  • C:\windows\system32\ntoskrnl.exe
  • C:\windows\system32\autochk.exe
  • C:\windows\system32\chkntfs.exe
  • C:\windows\system32\shutdown.exe
  • C:\windows\system32\ntkrnlpa.exe
  • C:\windows\system32\alg.exe
  • C:\windows\system32\bootok.exe
  • C:\windows\system32\chcp.exe
  • C:\windows\system32\ctfmon.exe
  • C:\windows\system32\dumprep.exe
  • C:\windows\system32\imapi.exe
  • C:\windows\system32\logon.exe
  • C:\windows\system32\MDM.exe
  • C:\windows\system32\recover.exe
  • C:\windows\system32\services.exe
  • C:\windows\system32\systray.exe
  • C:\windows\system32\win.exe
  • C:\windows\system32\wowexec.exe
  • C:\windows\system32\wuauclt.exe

* Deletes the following Registry tree branches:

  • HKCR\
  • HKLM\HARDWARE
  • HKLM\SAM
  • HKLM\SECURITY
  • HKLM\SOFTWARE
  • HKLM\SYSTEM
  • HKCC\Software
  • HKCC\System
  • HKCU\Software\Microsoft\Internet Explorer\Desktop\SafeMode
  • HKCU\Printers
  • HKCU\SessionInformation
  • HKLM\SYSTEM\ControlSet001\Control\SafeBoot
  • HKLM\SYSTEM\\ControlSet003\\Control\\SafeBoot
  • HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot
  • HKLM\SYSTEM\MountedDevices
  • HKLM\SYSTEM\LastKnownGoodRecovery
  • HKLM\SYSTEM\ControlSet001\Control\ContentIndex\Catalogs\System
  • HKLM\SYSTEM\ControlSet001\Control\Biosinfo

* Shows a fake error messagebox:

* Periodically sends the following message through mIRC chat client:

  • http://www.angelfire.com/celeb2/picsx/britney.jpg <- uuh, check it out !! :D

The above changes usually severely damage Windows operating system and it has to be reinstalled.