It’s just another day as you slide into your seat and hit the start button on your computer. You guzzle coffee as you wait for your system to start up, and bam! Your stomach drops as you stare at the deep indigo colored screen. It’s not a folk tale, it’s not an urban legend…it’s the blue screen of death. (BSOD) Yikes. There goes your day.

We all know that it’s common sense to stay away from funny looking email. If you don’t know who sent it, don’t open it. It’s a great concept, in theory. In fact, lots of us with itchy, trigger-happy fingers have opened email titled ILOVEYOU only to be bitten by the love bug. Ouch. Let’s take a look at some of the worst network attacks of all time.

ILOVEYOU ─ 2000
The ILOVEYOU is one of the first viruses to trick users into opening a file. The virus used mailing lists as its source for targets, so the messages appeared to come from someone known to the user, such as a friend or relative, making it seem safe to open. In reality, the file was a VBS script with an avalanche of junk mail that deleted thousands of files, including multimedia, music, and personal files. The author is not known, but it started in the Philippines.

Nimda ─ 2001
Built on Code Red’s attack system of finding multiple avenues into machines such as email, websites, and network connections, Nimda (admin backwards) computer worm infected Web servers and user machines. It was so effective it managed to leave a wide trail of casualties in its wake a mere 22 minutes after it was released. Nimda heavily impacted users of Windows programs. Some groups linked Nimda to Al-Qaeda because of the massive and quick destruction it caused, but this theory was dismissed. The author of Nimda remains unknown but left $635 million in destructive damage.

Slammer ─ 2003
The Slammer computer worm spread rapidly, infecting most of its 75,000 victims within ten minutes. When routers started to crash, it slowed the Internet to a crawl and shut down thousands of websites. The Slammer was named by Christopher J. Rouland because of it’s sudden effect. Although named SQL Slammer, it did not use SQL language. 22,000 systems were affected worldwide and South Koreans reported Internet shut downs for hours nationwide on January 25^th, 2003.

MyDoom ─ 2004
When MyDoom hit the scene it became the fastest-spreading computer worm of all time. Once it succeeded to infect computers, it would in turn send even more junk mail through infected computers with the subject “andy; I’m just doing my job, nothing personal, sorry”. There was speculation that MyDoom was used to attack the website of SCO Group, in retaliation of legal actions against a Linux or open source supporter. This claim since then has been dismissed and denied. The Author of this worm is not known.

Storm ─ 2007
The storm, a backdoor Trojan horse, swooped in and infected thousands of computers using an email with a subject line about a weather disaster. A Trojan likely appears to perform a specific action, but destructs and infects through a virus attack by performing something completely different. Trojans install backdoor programs. It mutated and spread via email spam with a fake attachment, and infected 10 million computers.

So is it over? Attackers continue to probe and sniff out weaknesses in hardware or software to gain access to networks, so take sensible precautions. In 2006, Malware resulted in $13.3 billion in damages across corporate America. Remember to avoid opening attachments or download programs that seem questionable or odd because it can take one click to bring down your company’s entire network.