Google announced today it is instituting a malware warning system on its search results page to alert users to the possibility that their computer is infected.
The Internet giant said it took the action after discovering unusual patterns of activity on the Web that it identified as a strain of malware that causes infected computers to send traffic to Google through proxy servers.
"Recently, we found some unusual search traffic while performing routine maintenance on one of our data centers," Damian Menscher, a Google security engineer, said in a Google blog post. "After collaborating with security engineers at several companies that were sending this modified traffic, we determined that the computers exhibiting this behavior were infected with a particular strain of malicious software, or 'malware.'"
The malware only affects computers running the Windows operating system, according to a post by Google engineer Matt Cutts. Systems can be tested by running a Web search for any word, he said.
Google said that as a result of its discovery, some users who come to Google through these specific intermediary servers will see a prominent notification at the top of their Google Web search results warning them of a possible infection.
"We hope that by taking steps to notify users whose traffic is coming through these proxies, we can help them update their antivirus software and remove the infections," Menscher said.
Google's Help Center also offers tips for scanning systems for malware and how to remove infections. Malware is often designed to disrupt normal computer operations or gather private information about the user.