Classification

Category :

Malware

Type :

Virus

Aliases :

Hamster

Summary

Hamster is a simple virus found from Norway at the end of April 1993. It managed to become quite widespread through bbs systems. Hamster infects COM-files in the current directory by appending it's own code to the end of the host files and patching the first three bytes to transfer the control to the viruscode.

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

Effective length of the virus is 546 bytes. It will infect all COM files unless they are already infected or if they are EXE files renamed to COM (the virus checks this by the magic number "MZ" in the beginning of EXE files).

Virus will not stay resident in memory, and it seems to infect one file at a time. It will not alter host files time or date fields.

The virus carries the names of the new and old host files within it's code. It also has one text string: "Turbo Hamster Virus!".