Threat Explorer

The Threat Explorer is a comprehensive resource consumers can turn to for daily, accurate, up-to-date information on the latest threats, risks and vulnerabilities.



21 March 2003
13 February 2007
Systems Affected:

VBS.HPWG.gen is a worm that infects file-sharing networks. The known variants spread through KaZaA, Morpheus, Grokster, and Bearshare, but do not do any damage.

Antivirus Protection Dates

  • Initial Rapid Release version 21 March 2003
  • Latest Rapid Release version 28 September 2010 revision 054
  • Initial Daily Certified version 21 March 2003
  • Latest Daily Certified version 28 September 2010 revision 036
  • Initial Weekly Certified release date 25 March 2003
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

VBS.HPWG.gen worms are generated by a tool that allows the creator of the worm to configure details, such as filenames, which file-sharing networks to infect, and which method to use for automatic startup. This type of worm may do any or all of the following:
  1. Copies itself to the %Windir% or %System% folder, using the same filename as the infected script.

    • %Windir% is a variable. The worm locates the Windows installation folder (by default, this is C:\Windows or C:\Winnt) and copies itself to that location.
    • %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 the lines:

    @Echo Off
    Start <filename>.vbs

    to the C:\Autoexec.bat file, so that the worm runs when you start Windows 95/98/Me.

  3. Adds the value:

    "<anything>" = "%Windir%\<filename>.vbs"

    to one the registry keys:




  4. Displays a fake error message.

  5. Copies itself to one or all of the following folders:
    • KaZaA\My Shared Folder
    • Grokster\My Grokster
    • Morpheus\My Shared Folder
    • Bearshare\Shared

      • These folders are located in the default Program Files folder. For example, C:\Program Files\Grokster\My Grokster.
      • The filenames vary, but are often pornographic in nature and always have a .vbs extension.


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.

The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.
  1. Update the virus definitions.
  2. Run a full system scan and delete all the files detected as VBS.HPWG.gen.
  3. Remove the lines added to the Autoexec.bat file. (Windows 95/98/Me).
  4. Delete the value that was added to the registry.

For specific details on each of these steps, read the following instructions.

1. Updating the virus definitions

Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:
  • Running LiveUpdate, which is the easiest way to obtain virus definitions: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
  • Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater).

    The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.

2. Scanning for and deleting the infected files
  1. Start your Symantec antivirus program and make sure that it is configured to scan all the files.
  2. Run a full system scan.
  3. If any files are detected as infected with VBS.HPWG.gen, note the filename, and then click Delete.

3. Removing the lines from the Autoexec.bat file
If you run Windows 95/98/Me, follow these steps:
  1. Click Start, and then click Run.
  2. Type the following:

    edit c:\autoexec.bat

    and then click OK. (The MS-DOS Editor opens.)

  3. Delete any lines similar to the following, if found.:

    @Echo Off
    Start <file name>.vbs

    NOTE: The exact path and filename may vary.

  4. Click File, and then click Save.

  5. Click File, and then click Exit.

4. Deleting the value from the registry

CAUTION : Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified keys only. Read the document, "How to make a backup of the Windows registry ," for instructions.
  1. Click Start, and then click Run. (The Run dialog box appears.)
  2. Type regedit

    Then click OK. (The Registry Editor opens.)

  3. Navigate to each of the keys:




  4. In the right pane, delete any value which refers to the filenames that the worm uses. For instance:


    NOTE: The exact path and filename will vary.

  5. Exit the Registry Editor.

Writeup By: Heather Shannon