Basic steps to avoid being hacked

Check if you see any of these common causes for security breaches:

1.- outdated blogs/cms software (third party applications)
2.- 777 permission on folders (galleries and upload folders)
3.- forums/software in general that allows uploads and don't check if the file
uploaded is really what it poses to be (an image for instance that is really
php code)

4.-Scan your computer in serach for viruses and trojans.
5.-Update all your web applications (like wordpress, joomla, etc)
6.- Change his site's password.

Hope this helps