Banner Ad Networks Used for Attacks
August 9, 2004 -- (WEB HOST INDUSTRY REVIEW) -- Several smaller banner ad networks have been used to inject malicious code into Web sites, according to research and analysis firm Netcraft (netcraft.com). In each of the cases, code for the banners serve as the trigger for a string of exploit scripts that trick Internet Explorer into downloading malware or spyware.

Because of their ability to place code on hundreds of outside sites, banner networks have become a vehicle for malware and virus distribution, the report said. And according to Netcraft, in an particularly alarming development, phishing scams have recently demonstrated a similar ability, installing keylogging trojans via banner ads.

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According to the report, SANS analyst Tom Liston has discovered a number of cases where banners have been used to install trojans and spyware.