During a year-long research effort, Google and university researchers found some 760,935 compromised websites across the web.

Google usually emails webmasters of the infections and up to three quarters of admins will expunge malware when emailed. However, they also found that 12 percent of the websites were re-infected within the month.

Our results indicate that browser interstitials, search warnings, and direct communication with webmasters all play a crucial role in alerting webmasters to compromise and spurring action," the researchers say.

"… we found Safe Browsing interstitials, paired with search warnings and WHOIS emails, resulted in 54.6 percent of sites cleaning up, compared to 43.4 percent of sites flagged with a search warning alone.

"Above all, direct contact with webmasters increased the likelihood of remediation to over 75 percent."

Google has urged admins to sign up to its Safe Browsing alerts.

Source: The Register