W32.Serflog.A

1. Closes Windows that contain the following strings in their titles:
   
   
   • ADWARE
   • ALERTS
   • ANTI
   • AUTOSTARTED
   • Avg
   • BENIGN
   • BLOCKER
   • BUG
   • BULLGUARD
   • BUSTER
   • CENTER
   • -CILLIN
   • CLEANER
   • CMD
   • Command
   • DESTROY
   • DETECTION
   • DOCTOR
   • EARTHLINK
   • EDITOR
   • ELIMINATE
   • EYE
   • FIGHT
   • Filter
   • FIREWALL
   • FIX
   • FIXING
   • HEAL
   • HELP
   • HUNTER
   • KERIO
   • Kill
   • LABS
   • LIVEUPDATE
   • MALWARE
   • MALWHERE
   • MCAFEE
   • NETCOP
   • NOD32
   • NORTON
   • PANDA
   • PROMPT
   • PROTECTOR
   • REGISTRY
   • REMOVAL
   • RESTORE
   • SANDBOX
   • SCAN
   • SECURE
   • SECURITY
   • SOPHOS
   • SPY
   • SPYBOT
   • SPYWARE
   • STOPPER
   • SWEEPER
   • TASK
   • TOOL
   • TREND
   • Update
   • VCATCH
   • VIRUS
   • WATCH
   • WORM
     
     Which may result in the following functions being disabled:
     
     
   • Registry editing programs
   • Command line
   • Process monitoring programs
   • Task manager
     
     
2. Creates the following mutex so that only one instance of the worm is run on the compromised computer:
   
   '-F-u-c-k-'-Y-o-u-'
   
   
3. Creates the following hidden copies of itself:
   
   
   • %System%\formatsys.exe
   • %System%\serbw.exe
   • %Windir%\msmbw.exe
   • %SystemDrive%\Crazy frog gets killed by train!.pif
   • %SystemDrive%\Annoying crazy frog getting killed.pif
   • %SystemDrive%\See my lesbian friends.pif
   • %SystemDrive%\LOL that ur pic!.pif
   • %SystemDrive%\My new photo!.pif
   • %SystemDrive%\Me on holiday!.pif
   • %SystemDrive%\The Cat And The Fan piccy.pif
   • %SystemDrive%\How a Blonde Eats a Banana...pif
   • %SystemDrive%\Mona Lisa Wants Her Smile Back.pif
   • %SystemDrive%\Topless in Mini Skirt! lol.pif
   • %SystemDrive%\Fat Elvis! lol.pif
   • %SystemDrive%\Jennifer Lopez.scr
   • %SystemDrive%\lspt.exe
   • %UserProfile%\Local Settings\Application Data\Microsoft\CD Burning\autorun.exe
     
     Notes:
   • %System% is a variable that refers to the System folder. By default this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).
   • %Windir% is a variable that refers to the Windows installation folder. By default, this is C:\Windows (Windows 95/98/Me/XP)or C:\Winnt (Windows NT/2000).
   • %SystemDrive% is a variable that refers to the drive on which Windows is installed. By default, this is drive C.
   • %UserProfile% is a variable that refers to the current user's profile folder. By default, this is C:\Documents and Settings\<Current User> (Windows NT/2000/XP).
     
     
4. Drops following hidden files:
   
   
   • %SystemDrive%\British National Party.jpg
   • %SystemDrive%\Crazy-Frog.Html
   • %SystemDrive%\Message to n00b LARISSA.txt
     
     
5. Opens a browser window and displays the file Crazy-Frob.Html
   
   
6. Displays the file Message to n00b LARISSA.txt in notepad.
   
   
7. Deletes the following file, if it exists:
   
   %SystemDrive%\MESSAGE_TO_BROPIA.txt
   
   
8. Adds the value:
   
   "[Value name]" = "[File name]"
   
   to the registry subkeys:
   
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
   HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\
   RunServices
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies
   \Explorer\Run
   HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
   HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\policies
   \Explorer\Run
   
   so that the worm is executed every time Windows starts.
   
   Where [Value name] is one of the following:
   
   
   • serpe
   • ltwob
   • avnort
     
     and where [File name] is one of the following:
     
     
   • %System%\formatsys.exe
   • %System%\serbw.exe
   • %Windir%\msmbw.exe
     
     
9. Sends a copy of itself to all the contacts in MSN Messenger using one of the following file names:
   
   
   • Crazy frog gets killed by train!.pif
   • Annoying crazy frog getting killed.pif
   • See my lesbian friends.pif
   • My new photo!.pif
   • Me on holiday!.pif
   • The Cat And The Fan piccy.pif
   • How a Blonde Eats a Banana...pif
   • Mona Lisa Wants Her Smile Back.pif
   • Topless in Mini Skirt! lol.pif
   • Fat Elvis! lol.pif
   • Jennifer Lopez.scr
     
     
10. Copies itself to the following folders, which are used by various file-sharing applications:
    
    
    • %SystemDrive%\My Shared Folder
    • %UserProfile%\Shared
    • %ProgramFiles%\Program Files\eMule\Incoming
      
      The worm copies itself to the above folders using the following file names:
      
      
    • Messenger Plus! 3.50.exe
    • MSN all version polygamy.exe
    • MSN nudge bomb.exe
      
      
11. Adds the text:
    
    OPEN=autorun.exe
    
    to the following file:
    
    %SystemDrive%\Documents and Setting\[Username]\Local Settings\Application Data\Microsoft\CD Burning\autorun.inf
    
    
12. Terminates the following processes:
    
    
    • apvxdwin.exe
    • atupdater.exe
    • aupdate.exe
    • autodown.exe
    • autotrace.exe
    • autoupdate.exe
    • avconsol.exe
    • avengine.exe
    • avsynmgr.exe
    • avwupd32.exe
    • avxquar.exe
    • bawindo.exe
    • blackd.exe
    • ccapp.exe
    • ccevtmgr.exe
    • ccproxy.exe
    • ccpxysvc.exe
    • cfiaudit.exe
    • cmd.exe
    • defwatch.exe
    • drwebupw.exe
    • escanh95.exe
    • escanhnt.exe
    • firewall.exe
    • frameworkservice.exe
    • icssuppnt.exe
    • icsupp95.exe
    • luall.exe
    • lucoms~1.exe
    • mcagent.exe
    • mcshield.exe
    • mcupdate.exe
    • mcvsescn.exe
    • mcvsrte.exe
    • mcvsshld.exe
    • msconfig.exe
    • msdev.exe
    • navapsvc.exe
    • navapw32.exe
    • nisum.exe
    • nopdb.exe
    • nprotect.exe
    • nupgrade.exe
    • ollydbg.exe
    • outpost.exe
    • pavfires.exe
    • pavproxy.exe
    • pavsrv50.exe
    • peid.exe
    • petools.exe
    • regedit.exe
    • reshacker.exe
    • rtvscan.exe
    • rulaunch.exe
    • savscan.exe
    • shstat.exe
    • sndsrvc.exe
    • symlcsvc.exe
    • taskmgr.exe
    • Update.exe
    • updaterui.exe
    • vpupd.exe
    • vshwin32.exe
    • vsstat.exe
    • vstskmgr.exe
    • w32dasm.exe
    • winhex.exe
    • wscript.exe
      
      
13. Adds the following text to the Hosts file to block access to various Web sites, some of which may be security-related:
    
    64.233.167.104 www.symantec.com
    64.233.167.104 www.sophos.com
    64.233.167.104 www.mcafee.com
    64.233.167.104 www.viruslist.com
    64.233.167.104 www.f-secure.com
    64.233.167.104 www.avp.com
    64.233.167.104 www.kaspersky.com
    64.233.167.104 www.networkassociates.com
    64.233.167.104 www.ca.com
    64.233.167.104 www.my-etrust.com
    64.233.167.104 www.nai.com
    64.233.167.104 www.trendmicro.com
    64.233.167.104 www.grisoft.com
    64.233.167.104 securityresponse.symantec.com
    64.233.167.104 symantec.com
    64.233.167.104 sophos.com
    64.233.167.104 mcafee.com
    64.233.167.104 update.symantec.com
    64.233.167.104 liveupdate.symantecliveupdate.com
    64.233.167.104 viruslist.com
    64.233.167.104 f-secure.com
    64.233.167.104 kaspersky.com
    64.233.167.104 kaspersky-labs.com
    64.233.167.104 avp.com
    64.233.167.104 nai.com
    64.233.167.104 networkassociates.com
    64.233.167.104 ca.com
    64.233.167.104 mast.mcafee.com
    64.233.167.104 my-etrust.com
    64.233.167.104 download.mcafee.com
    64.233.167.104 dispatch.mcafee.com
    64.233.167.104 secure.nai.com
    64.233.167.104 updates.symantec.com
    64.233.167.104 us.mcafee.com
    64.233.167.104 liveupdate.symantec.com
    64.233.167.104 customer.symantec.com
    64.233.167.104 rads.mcafee.com
    64.233.167.104 trendmicro.com
    64.233.167.104 grisoft.com
    64.233.167.104 sandbox.norman.no
    64.233.167.104 www.pandasoftware.com
    64.233.167.104 uk.trendmicro-europe.com
    
    
14. Modifies the following values:
    
    "DisableConfig" = "0"
    "DisableSR" = "0"
    
    in the registry key:
    
    HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows NT\SystemRestore
    
    to disable System Restore.

Recommendations

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

• Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
• Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
• Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
• Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
• Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
• Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
• If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
• Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
• Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
• Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
• Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
• If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
• For further information on the terms used in this document, please refer to the Security Response glossary.