From the HP Security Labs blog
If Google detects that your website is hosting malware, it is pretty clear your site has been attacked. A frightening trend with SQL Injection attacks concerns how an attacker will insert links to javascript content used to serve malicious links that may try and automatically compromise the users of your website. When this happens, Google will automatically detect this and actively deter users from visiting your website.
Here are some of the basic recovery steps that need to be taken to ensure all content that was possibly modified by the attacker will be removed. The steps below are simply a very rough set of guidelines on one way that a security analyst might approach securing a hacked website. Read the full story [hp.com]