A01 chaf6542 06 se fm indd

 Boot-  sector  virus

Occupies boot record 

of hard and floppy disks 

and is activated during 

computer start-up.

Worm

A small program that  self- 

 replicates and transfers 

across a network from 

machine to machine. A 

form of virus.

Trojan

A virus that masquerades 

as a bona fide application.

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Part 3  Implementation

virus writers is that the programs can be much larger. One of the most famous Trojans 

is ‘Back Orifice’, reputedly developed by a hacking group known as ‘Cult of the Dead 

Cow’. This could be attached to other larger files and gave complete access to a machine 

for a hacker.

6 

Hoax email viruses. These are warnings about  non-  existent viruses which ask the recipi-

ent to send the warning on to their friends. They are usually malicious, but can contain 

instructions on how to remove the virus by deleting files which could cause damage. They 

cause disruption through time lost.