Johannesburg - The digital super highway or the internet celebrates its 40th anniversary this year, and along with all the useful information and hours of fun it provides, it also has a dark side. Viruses.
And just as in the bio-physical world, online viruses are able to adapt and evolve.
According to Bulent Teksoz, a security expert at Symantec, the incentive among the writers of modern-day computer virsues is no longer fame, but financial gain.
"Viruses are written to be as silent as possible on the computers. Waiting stealthily on infected machines," said Teksoz in an e-mailed response to Fin24.com questions.
"Nowadays it is about stealing confidential personal information for financial gain and not about attracting attention," he said.
Luckily, it takes only a day to counter a new viruses, or hours in the case of particularly virulent strains that may make themselves on to desktops, notebook and laptops.
But Teksoz warns against buying freely available software online, especially if the product doesn't offer any support.
"An anti-virus (AV) software is designed to protect you against threats and only as good as the team that supports it," he said.
"The updates, definitions, signatures are all needed to get a good AV going. If it's 'free', who can guarantee that it actually is not a threat itself."
In acknowledgement of the impact viruses have made in our lives, we present the equivalent of a virus top 10 hit parade.
1. Morris (1988)
An oldie, but a goodie. Without Morris the current threat "superstars" wouldn't exist. The Morris worm (or Internet worm) was created with innocent intentions.
Robert Morris claims that he wrote the worm in an effort to gauge the size of the Internet. Unfortunately, the worm contained an error that caused it to infect computers multiple times, creating a denial-of-service.
2. Melissa (1999)
Melissa was an exotic dancer and David L Smith was not only obsessed with her, but also with writing viruses. The virus he named after Melissa and released to the world on March 26 1999, kicked off a period of high-profile threats that rocked the internet between 1999 and 2005.
3. I Love You (2000)
Who wouldn't open an e-mail with "I Love You" in the subject line? Well, that was the problem. By May 2000, 50 million infections of this worm had been reported. The Pentagon, the CIA, and the British parliament all had to shut down their e-mail systems in order to purge the threat.
4. Nimda (2001)
A mass-mailing worm that uses multiple methods to spread itself, within 22 minutes, Nimda became the internet's most widespread worm. The name of the virus came from the reversed spelling of "admin".
5. Code Red (2001)
Websites affected by the Code Red worm were defaced by the phrase "Hacked by Chinese!". At its peak, the number of infected hosts reached 359 000.
6. Slammer (2003)
This fast-moving worm managed to temporarily bring much of the internet to its knees in January of 2003. The threat was so aggressive that it was mistaken by some countries to be an organised attack against them.
7. Blaster (2003) Blaster is a worm that launched a denial-of-service attack against windowsupdate.com, which included the message: "Billy Gates why do you make this possible? Stop making money and fix your software!".
8. Sasser (2004)
This nasty worm spread by exploiting a vulnerable network port, meaning that it could spread without user intervention. Sasser wreaked havoc on everything from The British Coast Guard to Delta Airlines, which had to cancel some flights after its computers became infected.
9. Storm (2007)
Poor Microsoft, always the popular target. Like Blaster and others before, this worm's payload performed a denial-of-service attack on www.microsoft.com. During Symantec's tests an infected machine was observed sending a burst of almost 1 800 emails in a five-minute period.
10.Conficker (2009)
The Conficker worm has created a secure, worldwide infrastructure for cybercrime. The worm allows its creators to remotely install software on infected machines. What will that software do? We don't know.
Most likely the worm will be used to create a botnet that will be rented out to criminals who want to send spam, steal IDs and direct users to online scams and phishing sites.
- Fin24.com