In total, 45 857 unique malicious, advertising, and potentially unwanted programmes were detected on users' computers in March 2009 according to Kaspersky Security Network.

"The launch of the new site by Google is not before time, however, as we originally identified the problem way back in our Q1 2007 web trends security report," said Yuval Ben-Itzhak, Finjan's chief technology officer.

This tidal wave of malware has led to Google has creating a custom search engine - Anti-Malvertising.com - designed to help advertising network customers conduct quick background checks. It researches a variety of independent, third party sites that track possible attempts to distribute malware through advertising.

This is a trend that Finjan's MaliciousCodeResearchCenter has followed. In 2008 it reported the high-volume banner ad server that delivered infected banner ads to many of the 14 000-plus websites registered to receive ads. The attack employed the random JS toolkit, a crimeware Trojan that infects the end user's machine and sends back information to the hacker.

"With the automation of crimeware, the rise in all malicious code will increase exponentially and endanger both an advertiser's brand as well as their customer's PCs," explained Yuval Ben-Itzhak, CTO of Finjan.
Advertisers will have to be vigilant to ensure that their ads are malware free both in the creation of the advertisements as well as the delivery.