1. Technology
You can opt-out at any time. Please refer to our privacy policy for contact information.

Boot Sector Virus

By

Definition:

A boot sector virus infects the boot sector of a drive and is spread via infected floppy disks. This usually occurs when users inadvertently leave a floppy disk in drive A:\. When the system is next started, the PC will attempt to boot from the floppy. If the disk is infected with a boot sector virus, that virus will infect the boot sector of the user's local drive (C:\).

Unless the floppy disk is a bootable system disk, the user will simply see a standard warning that the drive contains a "non-system disk or disk error" and the user will be prompted to "replace the disk and press any key when ready". Most users will realize a floppy has been left in the drive, remove it, and reboot the system, unaware they may have just infected their system with a boot sector virus.

Compared to other types of malware, a boot sector virus can be fairly benign - simply taking room up in memory. However, a boot sector virus can also contain a malicious payload.

The simplest method to prevent a boot sector viruses is to change the CMOS settings to boot from the local C:\ drive first, rather than from floppy. Most modern BIOS is already configured to boot from the hard drive first.

  1. About.com
  2. Technology
  3. Antivirus Software
  4. Antivirus Glossary
  5. Boot Sector Virus: Antivirus Glossary

©2014 About.com. All rights reserved.