Safe Software to Combat Viruses
Computer viruses have been around for many years, but earlier this month they became international news thanks to a Cornell University student who wrote a program that slowed thousands of computers to a crawl. The infection of the Defense Department’s Arpanet network affected research computers throughout the world. No personal computers were affected--only larger systems from Sun Microsystems and Digital Equipment--but PCs definitely are vulnerable to virus attacks.
John McAfee, chairman of the Computer Virus Industry Assn., says his organization has recorded 300 “events” during the past eight months that affected more than 48,000 computers. He says 97% of the incidents involved personal computers, which he considers more vulnerable than larger systems. That’s because people commonly stick their disks into other people’s computers, to share data or software or just to use someone else’s printer.
Exchanging data, according to most experts, is not very risky. The real danger comes when you exchange software. Viruses spread by attaching themselves to programs. Once infected, a program can spread the virus to other programs and other computers.
McAfee’s group has logged 30 strains of viruses that affect PCs. Some are innocuous pranks. One virus, called the “peace virus,” attached itself to the operating system of thousands of Apple Macintoshes and simultaneously displayed a message about world peace. Then it went away, causing no damage. Others have destroyed data on hundreds of hard disks. Still others, according to McAfee, have made minor but potentially disastrous modifications to data files like moving a decimal point or adding a zero. Some viruses do their dirty deeds right away, while others act like time bombs, going off at a set time.
Peter Norton, the author of the popular Norton Utility programs, cautions people not to become hysterical over the threat of viruses. He likens many of the reported incidents as “urban myths, like alligators in the New York sewers.” In an apparent effort to calm computer users’ fears, the Washington-based Software Publishers Assn. on Wednesday announced that it had formed a group to evaluate new viruses.
Only 4% of cases reported to the Computer Virus Industry Assn. are verified as real viruses. Most are software bugs, system errors or similar problems.
Some software publishers have produced “vaccines” to protect computers against potential viruses. McAfee, who is president of Interpath, a San Jose company that makes vaccines, says that while no vaccine is 100% effective, they reduce the danger.
There are three classes of vaccines. So-called infection-prevention programs effectively stop about 75% of the viruses from taking hold in a computer system, according to McAfee.
Another type, infection-detection programs, alerts you when your computer has been infected but doesn’t do anything about curing the problem.
A third group, infection-identification and removal programs, identify and neutralize certain known viruses. They’re good for the viruses they recognize but can’t protect against unforeseen strains.
HJC Software of Durham, N.C., makes Virex, an infection-identification and removal program for the Apple Macintosh. The program, according to the company, combats the three Macintosh viruses “that are currently known.”
Prevention is, of course, the best defense. To reduce your risk to near zero, avoid exchanging programs with other people. Don’t use software unless it’s from a reliable software firm, and make sure you unwrap the package yourself. Before you copy programs to your hard disk, set the “write protect” tab on the source disk to make sure it doesn’t pick up a virus from the hard disk.
It’s also important to back up, or copy, your data on a regular basis. Keep several backup copies around, just in case one gets infected.
If you’re on a local area network, be certain that only authorized personnel can upload--that is, transfer--programs to the network itself. As the Arpanet incident demonstrated, a virus on a network can infect many of the machines that are connected.
And make sure that no one can tamper with your computer. If your machine is accessible to others, it’s possible for someone to plant a virus or erase files.
There is no danger in sending messages or reading news and other information from the Source, Compuserve, MCI Mail or other electronic information services. Nor is there a risk in logging on to the free public electronic bulletin boards. You are at risk, however, if you use software that has been downloaded (copied) from such services. Although the people who run these services strive to keep them clean, it is impossible to guarantee that every program is virus-free. The same is true with public domain or shareware programs that are passed around on floppy disks. The safest way to get shareware is to order it directly from the author, usually for a nominal fee.
Ironically, viruses could deter one of the software industry’s biggest problems--illegal copying of software. People who use illegal copies of software are particularly at risk to viruses. Regardless of whether you feel morally or legally obligated to pay for your programs, you should stick to legitimate copies for your own protection.
Asking people to avoid public domain software and bulletin boards is like preaching celibacy. It’s difficult to give up something that is enjoyable. And while there is some risk, I don’t plan to abandon the practice entirely. From now on, however, I’ll only use electronic information services that require users to register their name and address, and I won’t accept floppy disks from strangers.
For a comprehensive information packet on viruses, send $2 with a stamped ($1.45 in postage), 8-by-11-inch envelope to the Computer Virus Industry Assn., 4423 Cheeney St., Santa Clara, Calif. 95054.
