The people with malicious intent that lurk about the internet would like nothing more than to ship their malware to unsuspecting computer users. In order to do this they have to set up specially crafted webpages that spread malware; or they have to compromise a legitimate site, your site.
“As we crawl the web, we see bad content inserted on to thousands of hacked sites each day. The number of sites attacked is staggering and the problem is only getting worse. Hackers and spammers target and successfully compromise any sites they can - small personal sites, schools and universities, even multinational corporations. Spam attacks against forums and user content sections of sites, though not as shocking, are even more widespread,” explained on behalf of the Search Quality Team, Jessica Wong and Jason Morrison.
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To help webmasters protect their sites, Google’s Webmaster Tools already notifies them when new software versions are available. To further help webmasters protect their sites, Google will start notifying more webmasters when the search engine giant suspects someone is trying to hack into the site, when forum pages receive huge amounts of spam comments, or when spammy or abused user-generated content is detected.
The notifications will provide webmasters with two crucial pieces of information. First of all they will alert them that something is not exactly right. Secondly it will guide them on how to get things fixed and how to get their site back amongst Google’s search results.
“We've been notifying webmasters of suspected hacking for years, but a recent upgrade to our systems will allow us to notify many more site owners that have been hacked. We hope webmasters will find these notifications useful in making sure their sites are clean and secure, ultimately providing a better user experience for their visitors. In the future, we may extend this effort even further to include other types of vulnerabilities or abuse issues,” added Jessica Wong and Jason Morrison.
The people with malicious intent that lurk about the internet would like nothing more than to ship their malware to unsuspecting computer users. In order to do this they have to set up specially crafted webpages that spread malware; or they have to compromise a legitimate site, your site. 
