Classification

Category :

Malware

Type :

Virus

Aliases :

Dementia

Summary

This is an unusual virus. It infects COM and EXE files normally, but is also able to infect ZIP files: virus inserts a file called CALLFAST.COM to any ZIP file when they are accessed. This file is a BBS advertisment for 'Dementia BBS' and is infected by the virus.

It seems that the virus has been written to faciliate stealing files from a BBS system. Virus checks any ZIP file for a file called REQUEST.IVA. If such a file is found, virus reads a filename list from this file, collects the files, encrypts them and adds them to the same ZIP file as file RECEIPT.IVA.

Dementia does not need external programs to modify ZIP files.

Dementia contains these texts:

Dementia
 Copyright 1993 Necrosoft enterprises
-
All rights reserved
 I am the man that walks alone
 And when I'm walking a dark road
 At night or strolling through the park
 When the light begins to change
 I sometimes feel a little strange
 A little anxious when it's dark

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

N/A