Category: Malware

Type: Virus

Platform: W97M


W97M/FF is a simple Word class infector.


Automatic action

Based on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the detected program or file, or ask you for a desired action.

Knowledge Base

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About the product

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Submit a sample

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Technical Details


When an infected document is opened, W97M/FF.A deletes the "Tools/Macros" menu and disables the built-in macro virus protection first. Then the virus creates a temporary file, "C:\FF.sys", and infects the global template.

Afterwards every opened document is infected.

the virus activates its payload on the first day of every month. It alters the "c:\msdos.sys" file by changing the


line to


This causes Windows 95/98 to start in command line mode after boot, instead of graphical user interface (GUI).


This variant is functionally identical with W97M/FF.A.