Have you been hacked? READ THIS
Do you think you have been hacked?
If so, unless you are running the latest version of Joomla, you probably won't get much sympathy from some of the users around here. Why? Because Joomla is amazingly quick to react to security exploits and patches are release when needed, often within hours.
So, before you post click here:
Joomla! Developer - Vulnerability News
Subscribe via email if you have not already done so.
Please don't try to blame 'Joomla' for your lack of security if your install is out of date.
Next, follow the link above:
Security Checklist