The Wall Street Journal has a chilling story (paid sub required, sorry) about hackers planting viruses in online banner ads. Click on the infected ad and bang! the payload lands in your computer. From WSJ.com:
In May, a virus in a banner ad on tomshardware.com automatically switched visitors to a Web site that downloaded “malware” — malicious software designed to attack a computer — onto the visitor’s computer. ScanSafe Inc., one of the first security firms to discover the virus, estimates the banner ad was on the site for at least 24 hours and infected 50,000 to 100,000 computers before Tom’s Hardware removed it.
This trend – call it the evolution of the spyware pop-up – could cause major headaches for members of the online ad ecosystem, from the advertisers to the publishers to, in particular, the network providers that serve up the ads. The complexity and automated nature of this supply chain will make it difficult to keep hackers out. With large chunks of ad budgets being shifted to online, this problem could quickly percolate into a full-fledged crisis. Just wait until malware starts showing up on web-enabled cell phones!
I knew I had a good reason for never clicking on web ads.