Postini expects to see a continued increase in spam levels in 2007, as globalisation leads to more personal computers attached to high-speed internet connections around the world.

Much of the increased volume of spam in 2007 is coming from bot-nets, which are networks of hijacked personal computers that spammers use to deluge the internet with ever increasing volumes of spam and viruses. Bot-nets allow spammers to send a virtually unlimited amount of spam at no cost by coordinating millions of compromised personal computers and network connections to send unwanted messages.

In December, hackers continued to demonstrate creativity and innovation in unleashing a widespread social-engineering based email virus known as the ‘Happy New Year’ worm. This single massive attack drove the daily volume of email-borne viruses on the internet upward by a factor of twenty on New Year’s weekend. The ‘Happy New Year’ worm, also known as Nuwar and Mixor, used social engineering techniques designed to exploit people’s expectations of legitimate New Year’s postcards and greetings from friends and family. The goal of the ‘Happy New Year’ worm was to steal personal information and to hijack the recipient’s computer to add it to bot-nets, spreading even more spam and viruses.

The top five viruses for December 2006 were:

Virus Name - Quantity Block
nuwar - 19,409,015
netsky - 6,497,291
stration.gen - 4,142,926
downloader-arl - 2,690,374
mytob - 2,196,045