Google's DoubleClick spreads malicious ads (again)

Google's DoubleClick ad network has once again been caught distributing malicious banner displays, this time on the home page of eWeek.

Unsuspecting end users who browse the Ziff Davis Enterprise Holdings-owned site were presented with malvertisements with invisible iframes that redirect them to attack websites, according to researchers at Websense. The redirects use one of two methods to infect users with malware, including rogue anti-virus software.

In one case, a PDF with heavily obscured javascript shunted victims to a subdomain at inside.com. (The PDF in not related to the zero-day vulnerability currently menacing Adobe Reader, Dan Hubbard, vice president of security research at Websense, says). In other scenarios, a generic index.php file did the bidding.