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Article ID: 259341 - Last Review: January 27, 2007 - Revision: 1.5

This article was previously published under Q259341


The New York Boot (NYB) virus is a simple Master Boot Record (MBR) virus. It is a stealth virus and is contracted when an infected floppy disk is started. The virus was previously known as Stoned.i, B1 and was discovered in 1995. This virus creates a copy of the uninfected MBR and stores it on the hard disk drive at side zero, cylinder zero, sector 17, and then places itself in the original location of the MBR. Any attempt to read the MBR is redirected to sector 17; NYB is a stealth virus because it uses this method to prevent detection.


This virus uses the last record of the root directory on floppy disks to hold its viral code. Any data that is written to this area is lost. There are two payloads with this virus:
  • In one out of every 512 floppy disk accesses, the virus causes the system to constantly scan the drive, which eventually leads to physical damage to the drive.
  • If the drive is written to at the exact second of midnight, the virus crashes the system, causing any unsaved data to be lost.
It is recommended that viruses be removed from the system with an anti-virus software program.

  • Microsoft Windows 98 Standard Edition
kbinfo kbvirus KB259341
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