W32.HLLW.Stiq

1. Creates the files:
   • C:\Windows\System\Systray_.exec
   • C:\Windows\System\Runtray_.dll.
     
     NOTE: Due to bugs in the code, both files do not work as designed, and therefore, Symantec antivirus products do not detect them.
     
2. Adds the value:
   
   SystemTray %windir%\systray_.exe
   
   to the registry key:
   
   HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
   
3. Modifies the (Default) value of the registry key:
   
   HKEY_CLASSES_ROOT\exefile\shell\open\command
   
   to:
   
   (Default) c:\windows\system\systray_.exe %1 %*
   
   in an attempt to execute the worm when you execute an .exe file. As a result, the .exe files will not run.
   
4. Modifies the file C:\Mirc\Script.ini, so that it can spread itself using mIRC. Symantec antivirus products detect the .ini file as W32.HLLP.STD.C.
5. Attempts to spread itself using Microsoft Outlook; however, due to a bug in the code, the worm will fail to do so. The message it attempts to send is:
   • Subject: The subject is one of following:
     • an adult screensaver slideshow program
     • a Microsoft Explorer Patch
     • a Desktop Game I got off the internet
     • a brand-new MP3 player and plug-ins
     • an Microsoft Internet Explorer Service Pack (Q401243)
     • an Kaspersky Anti-Virus 4.0 bugfix
     • Here it is
   • Message: The Message is one of following:
     • Here is the e-mail attachment I told you about earlier, It's an installation program for an Outlook Service Release upgrade.
     • Hey, sorry I haven't written to you in a while. Well you could call it a while. I'm writing this E-mail to let you know of an attachment im sending with the next mail.
   • Attachment: install_.exe.
     
6. Deletes these files:
   • C:\Program Files\Norton AntiVirus\*.dat
   • C:\Program Files\Kaspersky Lab\Kaspersky Anti-Virus Personal Pro\*.*
   • C:\Program Files\Common Files\KAV Shared Files\*.*
     
7. Adds or modifies these values:
   
   bVShieldEnabled dword:00000000
   CurrentVersionNumber 666
   DAT NONE
   DATFILE -2000
   SerialNum MYST v1.0 by MYSTiQUE
   VirusInfoURL http:/ /mafia.sexchat.ru
   
   in the registry key:
   
   HKEY_LOCAL_MACHINE\Software\McAfee\Scan95

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.