W32.HLLP.Gosusub

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Discovered: January 29, 2002
Updated: February 13, 2007 11:51:29 AM
Type: Virus


W32.HLLP.Gosusub is a virus that infects most executable files on all local drives and mapped network drives. It deletes all .txt files that it finds. This virus contains bugs that may cause it to corrupt executable files when it infects them.

Antivirus Protection Dates

  • Initial Rapid Release version January 30, 2002
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version January 30, 2002
  • Latest Daily Certified version September 28, 2010 revision 036

Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Writeup By: Atli Gudmundsson

Discovered: January 29, 2002
Updated: February 13, 2007 11:51:29 AM
Type: Virus


W32.HLLP.Gosusub is a prepending virus that was written in a high-level language (HLL), such as C++; thus, the HLLP name.

When it is executed, the virus performs the following actions:

It creates the file C:\Windows\Win386.exe.

It then adds the value

win386     C:\WINDOWS\win386.exe

to the registry key

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

This virus also modifies the System.ini file to contain the following line:

shell=explorer.exe win386.exe

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.

Writeup By: Atli Gudmundsson

Discovered: January 29, 2002
Updated: February 13, 2007 11:51:29 AM
Type: Virus


To remove this virus, repair files that are detected as W32.HLLP.Gosusub, remove the value that the virus added to the registry, and remove the text that it added to the System.ini file.

To remove the virus:

  1. Run LiveUpdate to make sure that you have the most recent virus definitions.
  2. Start Norton AntiVirus (NAV), and make sure that NAV is configured to scan all files. For instructions on how to do this, read the document How to configure Norton AntiVirus to scan all files.
  3. Run a full system scan.
  4. If any files are detected as infected by W32.HLLP.Gosusub, click Repair. Files that cannot be repaired, or that no longer function after you try to repair them, should be replaced from a clean backup or reinstalled.

To edit the registry:

CAUTION : We strongly recommend that you back up the registry before you make any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify only the keys that are specified. Read the document How to back up the Windows registry for instructions.
  1. Click Start, and click Run. The Run dialog box appears.
  2. Type regedit and then click OK. The Registry Editor opens.
  3. Navigate to the following key:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
  4. In the right pane, delete the following value:

    win386     C:\WINDOWS\win386.exe
  5. Click Registry, and then click Exit

To edit the System.ini file:
Follow these steps only if you are running Windows 95/98/Me.
  1. Click Start, and click Run.
  2. Type the following, and then click OK:

    edit c:\windows\system.ini

    The MS-DOS Editor opens.

    NOTE: If Windows is installed in a different location, make the appropriate path substitution.
  3. Locate the line that begins with shell=explorer.exe
  4. Position the cursor immediately to the right of the ".exe" in "explorer.exe"
  5. Delete the text win386.exe

    The line should now look like:

    shell=explorer.exe

    NOTE: Some computers may have an entry other than Explorer.exe after shell=. If this is the case and you are running an alternative Windows shell, then change this line to shell=explorer.exe for now. You can change it back to your preferred shell after you have finished this procedure.
  6. Click File, click Exit, and then click Yes when you are prompted to save the changes.


Writeup By: Atli Gudmundsson