Int10 is an unusual boot sector virus. It infects MBRs on hard drives and floppy boot sectors.

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.

For more Support

Knowledge Base

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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

When an infected machine is booted from the hard drive, Int10 removes itself temporarily from the MBR and INT 13h chain in order to hide it's presence. When DOS has been loaded, it reinfects the MBR.

Int10 does not appear to be deliberately malicious. It activates at midnights during December or six hours after the machine has been booted (again, only in December). At this time it displays a graphic snowfall on-screen and halts the machine.

Int10 is encrypted with a simple key.

There are three known variants of this virus.