VBS.Seeker.Family

SUMMARY

VBS.Seeker.Family is a Visual Basic Script (VBS) Trojan horse that alters the Internet Explorers home page and search page.

Protection

• Virus Definitions (Intelligent Updater) January 17, 2002

TECHNICAL DETAILS

When VBS.Seeker.Family is executed, it looks at the following registry keys:

HKEY_CURRENT_USERSoftwareMicrosoftInternet ExplorerMainStart Page
HKEY_CURRENT_USERSoftwareMicrosoftInternet ExplorerMainSearch Bar

If they are not are already set to the pages that have been programmed by the hacker, or if they are set to local files, it sets them to its own home and search pages.

It will then adds an address to the \%Windows%hosts file to map the address

auto.search.msn.com

to its own site.

NOTE: %Windows% is a variable. The worm locates the Windows folder (by default this is C:Windows or C:Winnt) and makes the changes in that location.

Recommendations

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

• Turn off and remove unneeded services. By default, many operating systems install auxiliary services that are not critical, such as an FTP server, telnet, and a Web server. These services are avenues of attack. If they are removed, blended threats have less avenues of attack and you have fewer services to maintain through patch updates.
• If a blended 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 (for example, all Windows-based computers should have the current Service Pack installed.). Additionally, please apply any security updates that are mentioned in this writeup, in trusted Security Bulletins, or on vendor Web sites.
• 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.
• Configure your email server to block or remove email that contains file attachments that are commonly used to spread viruses, such as .vbs, .bat, .exe, .pif and .scr files.
• Isolate infected computers quickly to prevent further compromising your organization. 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.

REMOVAL

To remove this Trojan, delete all files detected as VBS.Seeker.Family, reset your Internet Explorer home page and search page, and delete the line that refers to auto.search.msn.com from the hosts file.

To remove the Trojan:

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. Delete all files that are detected as VBS.Seeker.Family.

To reset the Internet Explorer home page:

1. Start Microsoft Internet Explorer.
2. Connect to the Internet and go to the page that you want to set as your home page.
3. Click Tools and then click Internet Options.
4. In the Home page section of the General tab, click Use Current, and then click OK.

To reset the Internet Explorer Search page:

1. Start Microsoft Internet Explorer.
2. Click the Search icon on the toolbar.
3. Click Customize.
4. Click Reset and then click OK.

To edit the Hosts file:
This file may not exist on all systems.

1. Using Windows Explorer, browse to the Windows or Winnt folder.
2. Locate the Hosts file (if it exists).
   
   NOTE: On some NT-based systems, this file may be in the I386 folder.
   
3. Right-click the Hosts file and then click Open With.
4. Choose Notepad and then click OK.
5. look for a line that refers to:
   
   auto.search.msn.com
   
   If you find it delete it.
6. Close Notepad and save your changes when prompted.