If your site has been recently hacked and you are trying to clean it up yourself, we recommend that you use SiteCheck Malware Scanner, our Free WordPress plugin to help you during that task.
The plugin has a collection of useful tools that can guide you along the way. The steps provided here are not final, and there are some variations that require more work, but by just following these steps, you will get very far. We will also not rely on any specific signature or malware strings, since those can easily be evaded by the clever bad guys.
As always, if you need professional help, the Sucuri team is here for you.