Den Zuk


This virus will seek out and destroy copies of the Brain virus. If it finds a Brain-infected diskette, it will remove the infection, and replace it with a copy of itself. This virus hides on track 40 on diskettes, but normally 360K diskettes only have tracks numbered 0 to 39. This virus does not infect 1.2M or 3.5" diskettes correctly, but will destroy data on them. The volume label "(c) Brain" on an infected diskette would be changed to


This is because YC1ERP is the call-sign of the author, Denny Yanuar Ramdhani.

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

    First check if your F-Secure security program is using the latest detection database 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.

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User Guide

See the user guide for your product on the Help Center.

Contact Support

Chat with or call an expert for help.

Submit a sample

Submit a file or URL for further analysis.

Technical Details

On a computer infected with this virus, pressing Ctrl-Alt-Del will not result in a simple reboot. Instead the text "DEN ZUK" will appear on the screen for a fraction of a second.

Then the computer will appear to reboot, but the virus will remain in memory.

Pressing Ctrl-Alt-F5 will produce a "true" reboot.

Variant:Ohio (Hacker)

This is an older version of the Den Zuk virus and is written by the same author. Den Zuk will also remove the "Ohio" virus if it is found.

The Mardi Bros virus appears related as well.