Virus:W97M/Walker

Classification

Category :

Malware

Type :

Virus

Platform :

W97M

Aliases :

Sattelite, SAT, Walker

Summary

On 23rd and 24th of May, 2000, F-Secure received several questions about the following email:

From: wahaha123 [LRXT@SEtl.fPjY.com]

 
Reply-To: wahaha123@usa.net

 
To: LRXT@SEtl.fPjY.com

 
Subject:
How are you?

 
Body:

 Please to 	

While this email contains a script, it is not malicious. It opens a new browser window and connects to a web site.It seems that this message is an unsolicited bulk email ("spam").

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

This virus encrypts and decrypts it's own code on-the-fly, making analysis and detection of the virus problematic. The encryption is done with multiple layers of XOR-based substitution.

Infection

Sattelite spreads whenever Word documents are opened or closed. It detects that it has already infected a document by searching for this text in the documents macros:

  • SATTELITE V1.5

The virus activates by modifying the registry so that the registered owner name of Microsoft Windows will be changed to:

  • ThE wEiRd GeNiUs

This will work only under Windows 95 and Windows 98.Sattelite was widespread in Northern Europe in early 1999.

Variant:Walker.E

Walker.E is a slightly modified variant from W97M/Walker.D. The difference is that this variant uses the following string as a marker:

  • SATTELITE V1.0

This variant does not alter the name of the registered owner of Windows.

Variant:Walker.L

W97M/Walker.L is an encrypted class infector that infects the global template when an infected document is opened. After the global template has been infected, the virus infects all documents that are opened or closed.The virus also lowers the security settings of Word 2000, and disables all selections from the "Tools/Macro" menu.It uses the following string to determine if the document is already infected:

  • [Bench]Garbage v2.0