What is a computer virus and how do you get one?
If you depend on the information stored on your personal computer, you need to understand how computer viruses spread, and you should use anti-virus software to reduce the chance that a computer virus will infect your programs and files.
A computer virus is a program that makes copies of itself and infects files. Computer viruses can spread to other computers and files whenever infected files are exchanged. Often infected files come as email attachments, even from people you know. The email senders have no idea that they are passing…
2. Sasser
Shaun Nichols: Just how much damage can a virus do? Well, take the Sasser worm as one example. This relatively simple little attack managed to cripple airlines, news agencies and even knocked out government systems.
Perhaps most frustrating, however, was that Sasser infection was very easy to prevent. The vulnerability which the attack exploited had been patched for months, and all users had to do was install the most recent security updates from Microsoft.
Sasser was a stark warning that has yet to be heard by many. Unpatched systems are still pervasive around the world, leaving…
4. Nimda
Iain Thomson: A week after the 11 September atrocities a new virus hit the internet in a big way. Nimda was one of the fastest propagating viruses in history, going from nowhere to become the most common virus online in 22 minutes, according to some reports.
The reason for this speed was that Nimda used every trick in the book to spread itself. It used email, open network shares, IIS vulnerabilities and even web sites to spread. It hit pretty much every version of Windows available and appeared all over the place.
In the paranoid days after…
6. Storm
Shaun Nichols: Before Conficker came around and got everyone worked into a lather, Storm was the big bad botnet on the block. First appearing in early 2007 as a fake news video on European flooding, the Storm malware menaced users for more than a year.
The huge botnet was also influential for its continued use of social engineering tactics. The malware disguised itself as everything from video files to greeting cards, and attacks were continuously refreshed to coincide with holidays and current news events.
While Storm has since been eclipsed by newer botnets, the name still brings…
8. Conficker
Shaun Nichols: The global catastrophe that wasn’t, the third form of the Conficker attack provided nice theatrics but little in the way of actual damage.
The premise was pretty simple: Conficker.C would spread to as many machines as possible throughout March. Each infected machine was given a huge list of domains, one of which would be contacted by 1 April.
The deadline made all the difference. Now, Conficker wasn’t just a simple malware infection, it was a ‘ticking time bomb’, and a looming menace that would unleash carnage. Or at least that’s what the story turned into…
10. Elk Cloner
Iain Thomson: Elk Cloner was written by a 15-year old high school student called Rich Skrenta as a practical joke. Unfortunately for him the joke turned bad very quickly.
The virus was developed for the Apple II system and was a boot sector virus that spread via floppy discs. Apparently Skrenta was a fan of pirated games and would swap them with his friends, sometimes with little messages added. After one too many of these infected discs, he devised a way to alter discs automatically and the Elk Cloner virus was invented.
It had little in…
All this panic over a simple strain of flu got us thinking about some of the more virulent computer pandemics that have hit in recent years. While a computer virus pales in seriousness to a human outbreak, malware attacks can still take a huge toll on businesses throughout the world.
The viruses below may not have been the most widespread or effective, although many of them were. Instead they are the ones that stick in the mind as being particularly notable. There are been so many over the years, and viruses will always be a part of computing now, but…
Computer viruses are proving to be highly complex but preventing viruses from infecting your computer systems is simple. Use two well-known brands of anti-virus software and keep them as current as possible.
Beyond that, there are some simple, common sense procedures that everyone should use, whether at work or in the home computing environment. Never open a file whose origins are unknown. In a simpler day, that wisdom only applied to executable files, or files that did something. They have the suffixes .exe, .com and .bat and each can start a program on your computer. These viruses spread through games…
How to protect from getting a virus?
In today’s world having anti-virus software is not optional. A good anti-virus program will perform real-time and on-demand virus checks on your system, and warn you if it detects a virus. The program should also provide a way for you to update its virus definitions, or signatures; so that your virus protection will be current (new viruses are discovered all the time). It is important that you keep your virus definitions as current as possible.
Once you have purchased an anti-virus program, use it to scan new programs before you execute or install…
