Recently, scammers were able to get fake ads past Google’s usually solid vetting. Unfortunately, some of the fake ads were for Amazon.com and showed up at the top of search results for the online retailer.
While these fake ads did not link directly to malware, they did link to tech support scams designed to trick users into thinking their computer was infected with malware. These scams instruct people to call a bogus support phone number, where a scammer continues the ruse and attempts to gain the user’s credit card number in order to pay for their “help” in getting rid of the non-existent malware.
For more information, see this article by Graham Cluley on his Hot for Security blog.