A computer virus is a computer program that can copy itself and infect a computer without the permission or knowledge of the user.
On one hand, viruses show us how vulnerable we are, disrupting productivity and doing billions of dollars in damages. On the other hand, they show us how sophisticated and interconnected human beings have become.
Computer viruses are called viruses because they share some of the traits of biological viruses. A computer virus passes from computer to computer like a biological virus passes from person to person .
Mydoom worm infected approximately a quarter-million computers in a single day in January 2004
In March 1999, the Melissa virus was so powerful that it forced Microsoft and a number of other very large companies to completely turn off their e-mail systems until the virus could be contained.
The ILOVEYOU virus in 2000 had a similarly devastating effect. In January 2007, a worm called Storm appeared -- by October, experts believed up to 50 million computers were infected .
Virus Year Estimated Damage CIH 1998 20M to 80M $ Melissa 1999 300M to 600M $ Code Red 2001 2.6B $ SQL Slammer 2003 shut down South Korea's online capacity for 12 hours Blaster 2003 2B to 10B $ Sobig.F 2003 5B to 10B $ MyDoom 2004 At its peak, slowed global Internet performance by 10 percent and Web load times by up to 50 percent Sasser 2004 Tens of millions of dollars
How Does a Virus Work??? Trouble Prepender Virus Program Start End
How Does a Virus Work??? Appender PE Infector Overwriter
A logic bomb is a piece of code intentionally inserted into a software system that will set off a malicious function when specified conditions are met.
"Malware" is short for mal icious soft ware and is typically used as a catch-all term to refer to any software designed to cause damage to a single computer, server, or computer network, whether it's a virus, spyware.
The term spyware suggests software that secretly monitors the user's behaviour, the functions of spyware extend well beyond simple monitoring.
Adware or advertising-supported software is any software package which automatically plays, displays, or downloads advertisements to a computer after the software is installed on it or while the application is being used.
False positives occur when an anti-virus program calls a good program bad. It’s like arresting the wrong person.
False positives are expensive
AV doesn’t search for the entire virus, just a portion of it.
Search Google for “elephant” and you get over 58 million hits. You just need to find a specific elephant. Searching for “rude elephant” narrows the results to 1.73 million. A search for “very rude elephant” finds us “Rudy, the very rude elephant.”