Viruses << >>

How does a Virus Work?

The viruses use different ways to work. Broadly speaking we can have following classification:

Direct Action: These virus acts whenever the infected file is executed. Normally while acting these viruses infect more files and on some event (Particular Date, Particular Time or some other combination) it triggers the payload designed for destruction. It may even do the destruction generally. Normally only File viruses choose direct action.

Indirect Action: These viruses remain active in memory and control the activities. Normally they steal the interrupts/activity call and uses it for the purpose of Action. The stolen interrupt routines are now routed through virus code and this helps the virus to take control before the execution of the actual interrupt routine.