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The worst viruses of all time
Brain, 1986
It all started here: Brain was
the first "real" virus ever discovered, back in 1986. Brain didn't really hurt
your PC, but it launched the malware industry with a bang and gave bad ideas to
over 100,000 virus creators for the next 2 decades.
Michelangelo, 1991
The worst MS-DOS virus
ever, Michelangelo attacked the boot sector of your hard drive and any floppy
drive inserted into the computer, which caused the virus to spread rapidly.
After spreading quietly for months, the virus "activated" on March 6, and
promptly started destroying data on tens of thousands of computers.
Melissa, 1999
Technically a worm, Melissa
(named after a stripper) collapsed entire email systems by causing computers to
send mountains of messages to each other. The author of the virus was eventually
caught and sentenced to 20 months in prison.
ILOVEYOU, 2000
This was notable for being
one of the first viruses to trick users into opening a file, which in this case
claimed to be a love letter sent to the recipient. In reality, the file was a
VBS script that sent mountains of junk mail and deleted thousands of files. The
results were terribly devastating- one estimate holds that 10 percent of all
computers were affected, to a cost of $5.5 billion. It remains perhaps the worst
worm of all time.
Code Red, 2001
An early "blended threat"
attack, Code Red targeted Web servers instead of user machines, defacing
websites and later launching denial-of-service attacks on a host of IP
addresses, including those of the White House.
Nimda, 2001
Built on Code Red's attack
system of finding multiple avenues into machines (email, websites, network
connections, and others), Nimda infected both Web servers and user machines. It
found paths into computers so effectively that, 22 minutes after it was
released, it became the Internet's most widespread virus at the time.
Klez, 2001
An email virus, Klez pioneered
spoofing the "From" field in email messages it sent, making it impossible to
tell if Bill Gates did or did not really send you that information about getting
free money.
Slammer, 2003
Another fast spreader, this
worm infected about 75,000 systems in just 10 minutes, slowing the Internet to a
crawl (much like Code Red) and shutting down thousands of websites.
MyDoom, 2004
Notable as the
fastest-spreading email virus of all time, MyDoom infected computers so they
would, in turn, send even more junk mail. In a strange twist, MyDoom was also
used to attack the website of SCO Group, a very unpopular company that was suing
other companies over its code being used in Linux distributions.
Storm, 2007
The worst recent virus, Storm
spread via email spam with a fake attachment and ultimately infected up to 10
million computers, causing them to join its zombie botnet.
