The truth about viruses

David Perry has been tackling viruses for ten years. He reminisces about Pakistani Brain and Disk Killer, but, he tells Toby...

David Perry has been tackling viruses for ten years. He reminisces about Pakistani Brain and Disk Killer, but, he tells Toby Poston, the most dangerous viruses are imaginary

What is a computer virus?
A computer virus is any program written to make copies of itself (replicate). We used to say that a virus needed to attach those copies to other executable code (or infect) but that is now not always the case.

Notice I said nothing about destructive viruses. A program that only makes copies of itself is still a virus. A program that wipes out your files but does not replicate itself is not a virus. There are Trojans, Worms, Logic Bombs, Vandals and Zombies and a whole world of other hostile code types out there, and problems can be a combination of more than one type at a time. We tend to call the whole lot malicious software, or 'malware'.

One of the first viruses to spread in the wild was the Pakistani Brain virus. Two brothers in Lahore, who own a computer shop, wrote it. The virus contained a sort of Ad for the store, with an address and telephone number!

How and why did you start working with viruses?
I was interested in viruses from the very first time I heard about them. My first virus-related job was in tech support with (PC-software guru) Peter Norton. I worked from the start on Norton Antivirus, starting with version 1.0 for DOS. This was near the beach in Santa Monica and we all used to watch the taping of Baywatch with binoculars from our ninth-floor offices. I don't think many customers in those days (1991) knew that the tech they were talking with was watching Pamela Anderson while fixing their computer. I went from technical support to running the various support forums online and met many of the now familiar virus experts in the world. I went from there to McAfee, to Cybermedia (at which time I became the local chapter president of the Help Desk Institute) to Trend Micro.

How do companies working online protect themselves from viruses?
The tools are all known, put perhaps not well enough. Don't rely on simple desktop protection, that is like putting the alarm on the money bag itself. Guard the doors of your information security with a firewall, and with server-based antivirus solutions. This is a very complicated situation and needs to be tailored to the needs of the enterprise in question.

What was the cleverest virus you have come across?
I thought Disk Killer was very clever. It would write a message to your screen: "Don't touch your keyboard! Disk Killer is working!" People would blindly accept that the computer would only tell them the truth, and let the virus go ahead and erase their whole drives. I have often said that viruses are not just a technological phenomenon, but a sociological one.

And the most dangerous?
Well, that is a good question. I could say CIH, because it introduced the code to erase a BIOS, but easily the most dangerous viruses are the imaginary ones. By this I mean that people's fears and misunderstandings about viruses might do more damage than the viruses themselves. In the movies viruses cause computers to burst into flames, they tip over oil tankers and crash alien spacecraft.

This misrepresentation causes all kinds of mischief, and real viruses don't destroy hardware - well not yet: never say never is one of the prime lessons in this field - but they destroy something far more important. Data. The computer is only there to work on your data.

What are the big virus threats for the future?
There is a danger in prediction: we will almost certainly see some sort of mobile phone malware in the not too distant future. The new applications of computers, you might say, will give us the best indication of the new virus directions. Maybe we will all get lucky and this will die away, but I don't think so.

Do virus fighters hang out together?
Absolutely. This is a very tight-knit club. It's competitive and co-operative, but also a science, and a business all at the same time. There is much that we all agree upon, and also much disagreement. I ate breakfast with six virus fighters this very morning.

CV: David Perry
David Perry has more than 25 years of experience in the technology sector, including more than 10 years working with industry-leading antivirus solution providers and educating the public about safe computing practices.

He speaks regularly at security events and with the media, and recently co-chaired a conference at the White House on the issue of public education and critical system security.

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