A Google malware researcher gave a rare peek inside the company s massive anti-malware and anti-phishing efforts at the SecTor conference. Attackers have taken to infecting legitimate sites for a number of reasons, one of which is that those sites will show up more prominently in Google search results. As much as 1.5 percent of all search result pages on Google include links to at least one malware-distribution site, he said. Google uses a huge number of virtual machines running completely unpatched versions of Windows and Internet Explorer.
Source: https://threatpost.com/inside-googles-anti-malware-operation-102610/74611/