Classification

Category :

Malware

Type :

Virus

Aliases :

WET, Lavot, W.E.T.

Summary

This boot sector virus is known to be in the wild in the Netherlands.

WET is only able to infect a hard disk when you try to boot the machine from an infected diskette. At this time WET infects the DOS boot sector on hard drive, and after that it will go Resident, to high DOS memory during every boot-up from the hard disk. When WET infects floppies, it does not save the original boot sector anywhere.

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

Most other boot sector viruses infect the MBR on hard drives, not the DOS boot sector.

Once WET gets resident to memory, it will infect practicly all non-writeprotected diskettes used in the machine. WET uses stealth mechanisms to conceal it's presence.

The following text string can be seen in infected boot sectors:

(c) 1990 W.E.T.

The virus is suspected to have been written signifantly later than the copyright statement implies.

WET also ovewrites the file system type in the boot sector with its own code. The side effect from this is that the DOS sys command can NOT be used to overwrite the boot sector on the hard drive - it will just produce an error.

WET is difficult to remove unless you have a program capable of disinfecting it. Contact F-Secure anti-virus support for more info.