Friday

Classification

Malware

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Friday

Summary

For more information on Word macro viruses, see the description of Concept.

WordMacro/Friday consists of several macros, all of which start with the text 'NOP'. However, the virus is not related to the WordMacro/NOP virus.

On every Friday the 13th the virus renames IO.SYS to I_O.SYS, making the machine unbootable if the operating system is Windows 3.x or Windows 95. On Friday the 13th the virus also encrypts all saved files with the password "Friday13".

In addition, the virus exits Windows between 11:00 and 11:59 on Saturdays, encrypts documents with a password equal to the last three letters of the document name on Saturdays, protect the document with a password equal to the first 4 characters of the document name on Thursdays before 11 or on Wednesdays, exits Windows on Wednesdays after 23:00, etc.

WordMacro/Friday was reported to be in the wild in Germany in January 1997.

Removal

Automatic action

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.

Suspect a file is incorrectly detected (a False Positive)?

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

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  • 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.

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Technical Details

N/A