W32.HLLW.Backzat.C

1. Displays this fake message:
   
   
   
   or:
   
   You should be ashamed of yourself, you are infected with BatzBack by L0NEw0lf
   
   
2. Copies itself as the following files, the attributes of which are set to Hidden:
   • C:\%Windir%\TASKMOAN.EXE
   • C:\%System%\BBbLWDB.Scr
     
     NOTES:
     • %Windir% is a variable. The worm locates the Windows installation folder and copies itself to that location. By default, this is C:\Windows or C:\Winnt.
     • %System% is a variable. The worm locates the Windows system folder and copies itself to that location. By default, this is C:\Windows\System (Windows 95/98/ME), C:\Windows\System32 (Windows XP), or C:\Winnt\System32 (Windows 2000/NT).
       
       
3. Adds the value:
   
   TaskSysStartBB C:\%windir%\TASKMOAN.EXE
   
   to the registry key:
   
   HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
   
   so that the worm runs when you start Windows.
   
   
4. Adds the value:
   
   SysTrayStartLW C:\%system%\BBbLWDB.Scr
   
   to the registry key:
   
   HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\
   CurrentVersion\RunServices
   
   so that the worm runs when you start Windows.
   
   NOTE: This key is not found on all the operating systems.
   
   
5. Locates the KaZaA transfer folder by retrieving the value date of the value name, DlDir0, in the registry key:
   
   HKEY_CURRENT_USER\Software\Kazaa\Transfer
   
   
6. If the KaZaA transfer folder exists, the worm copies itself as:
   • C:\My Downloads\NUDIE SCREENSAVER.Scr
   • C:\Program Files\Grokster\My Grokster\KOF2K2.zip.EXE
   • C:\Program Files\ICQ\Shared Files\GAMECUBE EMU REALWORKING.EXE
   • C:\Program Files\EDonkey2000\Incoming\EminEmSpearsBritney.Scr
   • C:\Program Files\BearShare\Shared\XBOX EMU REALWORKING.EXE
   • C:\Program Files\Morpheus\My Shared Folder\HOT SEXY SCREENSAVER.Scr
   • <The KaZaA transfer folder>\Kira Kerner SCREENSAVER.Scr
     
     NOTE: The Grokster, ICQ, eDonkey2000, BearShare, KaZaA, or Morpheus software must be installed on the computer for the worm to spread in those networks.
     
     
7. Copies itself as C:\Program Files\AIM95\Buddies4Eva.Scr.
   
   
8. Creates the file, C:\%Windir%\Script.ini, which the worm uses to send copies of itself to other mIRC users.
   
   
9. Creates the file, C:\%Windir%\BBbLWDB.Bat, and runs it. The attribute of the file is set to Hidden. This batch file is a component of the worm. The worm uses this component to perform the following actions:
   • If any drives labeled G through Z exist, the worm copies itself to the root of these drives as Taskmoan.exe.
   • Searches the computer for some popular antivirus products, the names of which are in a list contained in the worm. If none of these antivirus products are installed, the worm uses Microsoft Outlook to send itself to all the contacts in the Outlook Address Book.
     
     The email has the following characteristics:
     
     Subject: Heyhey!
     Message: Ya know man, I've seen funny things in my life but this screen saver beats them all, You have to check this out.
     Attachment:BBbLWDB.Scr
     
   • If the installed operating system is Windows XP, Windows NT, or Windows 2000, the worm attempts to overwrite all the .exe files with itself. Otherwise, the worm attempts to overwrite all the .exe files in the C:\_RESTORE\Temp folder.
   • Attempts to append its component C:\%Windir%\BBbLWDB.Bat to all the .bat files.
   • If the system day is Sunday, the worm formats drives D, E, and F.
     
     NOTE: Due to bugs in the worm's code, the behavior described in this step has not been duplicated during tests in the Symantec Security Response antivirus lab.
     
     
10. The code in the worm also suggests that the worm may attempt to delete all the files in the following folders:
    • C:\PC-Cil~1
    • C:\ToolKit\FindVirus
    • C:\AntiVi~1
    • C:\VS95
    • C:\TBAVW95
    • C:\f-macro
    • C:\eSafen
    • C:\Progra~1\FindVirus
    • C:\Progra~1\FWIN32
    • C:\Progra~1\QuickH~1
    • C:\Progra~1\AntiVi~1
    • C:\Progra~1\Grisoft\AVG6
    • C:\Progra~1\AvPersonal\*.*
    • C:\Progra~1\Trojan~1\*.*
    • C:\Progra~1\Kasper~1\*.*
    • C:\Progra~1\TinyPe~1\*.*
    • C:\Progra~1\ZoneLa~1\ZoneAlarm\*.*
    • C:\Progra~1\Comman~1\F-PROT95\*.*
    • C:\Progra~1\TrendM~1\Pc-cil~1\*.*
    • C:\Progra~1\PandaS~1\PandaA~1\*.*
    • C:\Progra~1\McAfee\VirusScan
    • C:\Progra~1\McAfee\McAfee FireWall\*.*
    • C:\Progra~1\Common~1\Symant~1\Script~1\*.*
    • C:\Progra~1\Common~1\Symant~1\*.*
    • C:\Progra~1\Symantec\*.*
    • C:\Progra~1\Norton~2
    • C:\Progra~1\Norton~1

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.