W32.Kwbot.C.Worm

1. Copies itself as one of the following:
   • %System%\System32.exe
   • %System%\Cmd32.exe
     
     The attribute of this copy is set to Hidden.
     
     NOTE: %System% is a variable. The worm locates the System folder and copies itself to that location. By default, this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).
     
     
2. Adds one of the following the values:
   
   SystemSAS system32.exe
   CMD cmd32.exe
   
   to these registry keys:
   
   HKEY_Local_Machine\Software\Microsoft\Windows\CurrentVersion\Run
   HKEY_Local_Machine\Software\Microsoft\Windows\
   CurrentVersion\RunServices
   HKEY_Current_User\Software\Microsoft\Windows\CurrentVersion\RunOnce
   
   so that the worm runs when you start Windows.
   
   
3. Creates the subkey, krypton, in the registry key:
   
   HKEY_Local_Machine\Software
   
   
4. May change the value data of the value, Shell, in the registry key:
   
   HKEY_Local_Machine\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
   
   to:
   
   explorer.exe C:\<The file name of the copy of the worm>
   
   
   For example, the value in this registry key may be changed to:
   
   Shell explorer.exe C:\Windows\system32\cmd32.exe
   
   In this way, the worm runs when you restart Windows 2000/NT/XP.
   
   
5. Creates one of the following folders:
   • %Windir%\UserTemp
   • %Windir%\User32
     
     
6. Copies itself into the folder that the worm created in the previous step using many different file names that the worm carried. The attributes of all the copies are set to Hidden.
   
   Some examples of these file names are:
   • Battlefield1942_bloodpatch.exe
   • NBA2003_crack.exe
   • UT2003_keygen.exe
   • Age of Empires 2 crack.exe
   • MediaPlayer Update.exe
   • iMesh 3.7b (beta).exe
   • KaZaA Speedup 3.6.exe
   • Download Accelerator Plus 6.1.exe
   • Network Cable e ADSL Speed 2.0.5.exe
   • Guitar Chords Library 5.5.exe
     
     
7. Adds the value:
   
   Dir? 012345:%Windir%\UserTemp
   
   or:
   
   Dir? 012345:%Windir%\User32
   
   (NOTE: "?" in these values represents a number that the worm has chosen.)
   
   to these registry keys:
   
   HKEY_Current_User\Software\Kazaa\LocalContent
   HKEY_Current_User\Software\iMesh\Client\LocalContent
   
   so that other KaZaA or iMesh users may download the files from the %Windir%\UserTemp or %Windir%\User32 folders.
   
   NOTE: For the worm to spread, it requires the KaZaA or iMesh software be installed on the computer.
   
   
8. Opens two randomly selected TCP and UDP ports to connect to the hacker.
   
   
9. Listens for the commands from the hacker using its own IRC channel. The commands allow the hacker to perform any of the following actions:
   • Upgrade the worm
   • Steal the system and network information from your computer and send it to the hacker
   • Download and execute files
   • Perform Denial of Service (DoS) attacks against a target, which the hacker selects
   • Send the worm to other IRC users

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.