FBI sees rise in computer crime (Reuters)

Reuters - Computer spying and theft of personal information have risen notably in the best removal software spyware year, costing tens of millions of dollars and threatening U.S. security, the FBI's cyber division head said on Wednesday.

A computer program capable of copying itself and infecting a computer without even the user's permission or knowledge is known as a computer virus. When the host of a computer virus is carried to an uninfected computer, then the virus spreads from one computer to the other. Viruses get transferred over a network, Internet or through removable mediums like floppy disk, CD and USB drive.

There are three basic categories of computer viruses which are boot infectors, system infectors and generic application infectors. The boot sectors of diskettes and hard disks are attacked by the boot infectors. During the first access of a diskette the virus transfers itself to the sector 0 of the diskette and best removal software spyware then spreads to the system that are booted from this diskette. The Pakistani Brain Virus is an example of a boot infector. The system infectors are found to be attached to the operating system modules and Lehigh virus is a typical example. The Generic application infectors have the capability to harm any application program. Well known viruses of this kind include the Israeli Virus and the Scores Virus.

There are various theories and controversies regarding the first known computer virus. But majority support the view that The Creeper was the first virus that was detected on ARPANET which happens to be the forerunner of the internet in the 1970s. It found its way through the TENEX operating system and had the capability to use any linked modem to dial out to all remote computers for the purpose of infecting them. There are again beliefs about "Rother J" to be the first computer virus to have appeared "in the wild" which means outside the lab or the single computer where it originated. But the truth is that, it was the first virus to infect computers "in the home". A boot sector virus called The Brain was the first PC virus which appeared in the wild. In 1986, Farooq Alvi Brothers from Pakistan created this virus with the aim of discouraging pirated copies of software written by them.

CIH and Melissa are two well known viruses which created disasters in the years 1998 and 1999 respectively. The estimated amount of damage that CIH created was 20 to 80 million dollars. This virus originated from Taiwan and Windows 95, 98, and ME executable files were its main targets. This virus found its residence in a PC's memory. Soon after its activation, it started overwriting data on the host PC' hard drive and as a result it made it inoperable. It also prevented boot-up of the host by overwriting the BIOS of the host. Although it caused disasters and losses at some point of time but it is not a serious threat nowadays because of the migrations to Windows 2000, XP, and NT which are not susceptible to CIH. Melissa caused an estimated damage of 300 to 600 million dollars. This was a word macro script that infected the business PCs. The rapid spread of the virus made Intel, Microsoft and other companies that were using Outlook to shut their total e- mail systems down! This virus used the e- mail lists of the user of Microsoft Outlook to e- mail itself in the form of a .DOC file as attachment. Unsuspected receivers opened the file and got their systems infected.

There are a number of destructive viruses like Blaster, Bagle, MyDoom, Sasserbut I LOVE YOU released in 2000 deserves special mention. This acted like Melissa by e- mail itself with an irresistible message: I love You. It even used to find the IDs and passwords of the users of infected machines to send e- mails to its author. The amount of damage was estimated as 10 to 15 dollars. The irony is that Philippines had no law against computer viruses at that time and so it failed to punish the author of I LOVE YOU who was from Philippines itself!

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