I mentioned in August last year that Google started to show malware warnings if you click on a search result from a harmful site. Now Google shows a message below the title of a search result: "This site may harm your computer." Even if you click on the title, you won't be able to visit the site: Google explains you once again that the site could be dangerous and recommends you to visit another search results or to change your query. The only way to visit the site is to copy the URL and paste it in the address bar, which is not an obvious or a trivial task for an ordinary computer user.Google explains: "this warning message appears with search results that we've identified as sites that may install malicious software on your computer. We want our users to feel safer when they search the web, and we're continuously working to identify such dangerous sites and increase protection for our users."
Unlike spam pages that try to deceive search engines and are penalized or removed from the index, these pages deserve their ranking, but users are strongly discouraged to visit them.
A study from McAfee SiteAdvisor conducted in December 2006 revealed that: "41.4% of [dangerous] sites exhibit poor e-mail practices, 24.5% contain risky downloads, 26.8% are scam sites, 32.3% link to other risky sites and 3.0% contain browser exploits." Also, 4.2% of Google's search results are dangerous sites.