The virus outbreaks of 2002 were less dramatic than the Code Red and Nimda scares of 2001. But this year's trends are very clear: The new target is the home user. Find out how to protect yourself, on tonight's "Tech Live."

Businesses took computer viruses seriously in 2002, meticulously scanning email, locking down networks, and educating corporate users about the danger of attachments. But on the home front users are transmitting viruses at an epic pace.

Infection, spam increasing

According to security firm MessageLabs, one out of every 212 email messages in 2002 contained a virus. That rate is up from 2001, when only one in 380 email messages contained a virus.

There's an even more alarming trend in the MessageLabs statistics: Thirty percent of all email is now unsolicited mail or spam.

Spam scams were extremely prevalent during 2002. Dr. Mose Soseke and a host of other Nigerian diplomats and exiles needed our help transferring their money out of the country. Authorities estimate thousands of victims fell for the scam, and now in the latter part of 2002 we're seeing even more sophisticated versions of the Nigerian scam where online auction sellers are scammed for thousands of dollars.

Klez: public enemy No. 1

MessageLabs confirms that Klez was the No. 1 virus of 2002, with 5 million copies seen by the security firm. The virus used ingenious spoofing techniques to hide the source of outgoing infected email.

For the better part of six months this reporter has received hundreds of email messages telling her that she's sending out infected Klez email, even though her PC is as clean as a whistle. Klez randomly picks address book entries and cached email addresses to put into the "From" field of outgoing email so as to hide the identity of the true sender.

Who's targeted

Viruses had less success with corporate attacks in 2002. Outbreaks such as Code Red and Nimda were nonentities this year. One trend in network attacks is malicious code written to exploit Linux vulnerabilities. A hole in Apache Web servers running on Linux led to a new worm called Linux.Slapper.

Mac viruses were practically nonexistent in 2002, as were PDA and cellphone viruses. In 2001 security analysts predicted a pending storm of mobile viruses and worms, but not one made any significant inroads.

Peer-to-peer file sharing services, especially KaZaA, were targeted more and more throughout the year. The Benjamin, Backdoor.K0wbot, Lolol, and Duload worms infected computers and then renamed themselves as enticing downloads. Once downloaded, they started the infection process all over again.

A unique form of attack via KaAaA, called "eight ball," emerged in December. The malicious code masqueraded as a KaZaA skin, but when installed it erased all music files on a victim's hard drive. In response KaZaA created its own form of file screening for malicious code, but the cat-and-mouse game of new code vs. old screening methods continues in the P2P world.

Nasty greetings

Another trend late in 2002 was e-greetings loaded with malicious code. Three specific threats gave email users varying degrees of annoyance. One popped porn up on users' desktops. Another raided their Outlook address books for email addresses to add to a spam database. Yet another installed spyware on people's computers.

Here's the virus bottom line: Make it your New Year's resolution to install an antivirus program, and open attachments and executable files with the utmost caution.