Computer Virus - Horror or Hype?
Dave Carlson - May 8, 1989
You are at your computer calculating how much that new car will cost you…typing a letter…or, maybe…just about to score a zillion points in Space Eaters. You gasp for air and hold your breath as the screen unexpectedly goes blank. In a few seconds your work returns. A bit confused, but quite relieved, you decide to continue. ZAP! The instant you touch your keyboard the screen display vanishes again. But this time, it doesn’t stay blank. As the speaker faithfully churns out the theme song from The Twilight Zone, the screen quietly displays (one painful letter at a time): H-a-v-e A N-i-c-e D-a-y -- if you can!
You may have a problem. The Computer Virus Industry Association (CVIA) reported that more than 400 virus infestations affected nearly 90,000 computers last year.1 The friendly message on your screen may be the work of a not-so-friendly computer virus. Now what?
Computer viruses: What are they? Where do they come from? How do I know if my computer is sick? How can I cure it? How do I keep it healthy? Answers to these and other questions follow. Read on to enter the micro-world of electronic critters.
DEFINITION – What are viruses?
“Viruses are very small organisms that do not appear to be alive. They reproduce only when inside a living cell.”2 A computer virus is not an organism, nor does it function inside a living cell. However, a computer virus exhibits the same type of behavior associated with its organic counterpart.
It is a malicious programming code (usually small) designed to:
- replicate itself within an operating environment,
- take over system resources,
- and alter or destroy programs or data files.
Viruses have three primary purposes: reproduction, survival, and some objective task.3
“To be truly effective, the virus must be passed unknowingly to the victim, do its work, and then disappear. The user may suspect hardware problems, power glitches, or perhaps his or her own software.”4
Viruses don’t walk to work. They hitch a ride with a legitimate program, inside a Trojan Horse, or on a Worm. Like its biological namesake, a computer virus must attach itself to a program or data file that the host victim will accept.
HISTORY – Where did viruses come from?
The first virus was created in 1959 by Frederick G. Stahl of Chesterfield, MO.5 It evolved in the early 1960s as a game called Core Wars, where participants created code to take over each other’s computer systems. The code (called Redcode), kept secret for nearly twenty years, was publicly revealed in a 1983 speech by Ken Thompson, a software engineer who had written an early computer operating system.6 In May 1984, the code was offered to the world by a leading scientific journal. Anyone who sent $2.00 received “brief guidelines for those who would like to set up a Core War battle of their own.”7
Since then, Core Wars has become a very popular sport. In 1986, The Computer Museum of Boston hosted the first annual Core War tournament. The tournament was so popular that it sparked the formation of the International Core Wars Society.8 Legitimate players of various code war events follow a very well-defined set of rules (sort of Geneva Convention of code war).
Unfortunately, there are hacker mercenaries who don’t follow the rules. They violate the Law of War and attack non-combatants. Their actions leave many innocent victims.
SYMPTOMS – How do I know if my computer has a virus?
It may or may not be obvious that your computer has a virus. If you have one, and it attacks, it soon will be obvious that something is wrong. Generally, if your computer suddenly starts doing strange things, and you have not changed what you have done in the past, you may have a virus. But, don’t cry wolf the instant you don’t understand what your machine is doing.
“Much of the concern about viruses has been exaggerated.”9 Often, the computer user reacts to a poorly-written program, experiences a power fluctuation, or is annoyed by some other mundane glitch.
Some common operations, other than viruses, can cause strange symptoms in your computer. Examples are:
PREVENTION – How do I keep my computer healthy?
- Memory conflicts, especially with Terminate-and-Stay-Resident (TSR) programs
- Operator error (examples):
- Experimenting with EDLIN or DEBUG when running a program
- Inserting the wrong file disk
- “So THAT’S what FORMAT C: and DEL *.* do!
- Typing the wrong command
- Power fluctuations (brown-outs, etc.)
- Programmer error (program bugs)
- Static electricity
- Worn-out or damaged disk (especially the hard drive)
Protecting your computer from a virus infestation is not difficult. Many of the safety measures depend “more on common sense than on obsessive fortress building.”10 There are commercial programs available to protect your system from attack. However, you can protect your computer from most viruses for free.
There are several ways to protect your computer from virus attack. There are simple, moderate, and advanced protection techniques. The easiest (and most important) step you can take to protect your system from any type of computer virus disaster is to safeguard original program and data disks. Unless the disk is copy-protected, make a backup copy and run programs from the backup or from your hard drive. When something goes wrong (and it eventually will), you can restore your hard drive or operating system from the original disks.
TREATMENT – How can I cure a “sick” computer?
There is only one guaranteed method to ensure that your computer is completely cured after a virus attack – reformat your hard disk, destroy infested floppy disks, and start over. This may seem rather drastic, but a computer virus will not go away with bed rest like an organic virus will.
Many sources offer programs to clean viruses out of infected computers. Most of the products probably will do what their authors claim the will do, but vendors of vaccine software admit that their products are effective only against identified viruses and probably will lag one step behind the latest mutant strains. “Some new viruses operate subtly with random and intermittent behavior to ensure survival.”11 “Once a virus is identified and removed from a system, one of the major challenges is to prevent reinfection.”12
Spawned by the war criminals of Code Wars, computer viruses represent a significant threat to computer systems. Computer users must learn to “protect against virus infection, detect the presence of viruses, prevent them from operating, and repair the damage they cause.”13 There is no easy solution to the virus problem, but the information in this paper should help you successfully face that challenge.
END NOTE CITATIONS:
1 John D. McAfee. Managing the Virus Threat: How MIS can protect data from the gremlins of today’s computer systems, Computerworld, 13 February 1989, 89.
2 William E. Shapiro, Ed. The New Book of Knowledge, 12th Ed. (New York: Grolier, 1978), S.v. “Viruses,” by Harry Rubin.
3 Howard W. Townsend. Advanced MS-DOS: Expert Techniques for Programmers (Indianapolis: Howard Sams, 1989), 63.
4 Townsend, 63.
5 A. K. Dewdney. A “Core War” bestiary of viruses, worms, and other threats to computer memories, Scientific American, March 1985, 14.
6 Scott W. Cullen. The Computer Virus: Is There a Real Panacea?, The Office, March 1989, 44.
7 A. K. Dewdney. In the game called “Core War” hostile programs engage in a battle of bits, Scientific American, May 1984, 14.
8 A. K. Dewdney. A program called “MICE” nibbles its way to victory in the first “Core War” tournament, Scientific American, January 1987, 14.
9 Judy Getts. Viruses and Trojans Strike – But Very Rarely, PC World, October 1988, 72.
10 Neil J. Rubenking. Infection Protection, PC Magazine, April 25, 1989, 193.
11 Edward J. Joyce. Software Viruses: PC-Health Enemy Number One, Datamation, October 15, 1988, 30.
12 Joyce, 28.
13 Angel Rivera, Mark Hahn, and others. A Manager’s Guide to Computer Viruses: Symptoms & Safeguards, (Northborough, MA: Computer Security Institute, 1989), 4.