Past couple of days a large number of websites created using WordPress were hacked on Linux based shared-hosting environments. The initial reports today were restricted only to Dreamhost, it has since become apparent that blogs hosted at GoDaddy, Bluehost and Media Temple have also been affected. The only thing in similar is that all of them are on shared servers.
The hacked web pages appear to have been infected with scripts, which not only install malware on users’ systems, but also prevent browsers like Firefox and Google Chrome, which use Google’s Safe Browsing API, from issuing an alert when users try to access the page. When Google’s search bot encounters such a specially crafted page, the page responds by simply returning harmless code. This camouflage strategy takes advantage of the browser switch normally used by developers to return browser specific code to suit functional variations in different browser, such as Internet Explorer and Firefox. (source: h-online).