URL injected

Just because it has the word ‘inject’ does not necessarily mean its malicious. In fact a malicious script would probably avoid naming itself anything suspicious.

In your case though the issue appears to be an issue with Ad Block Plus, and not something specific to your site: https://issues.adblockplus.org/ticket/6744

Those are all security problems, but they have nothing to do with the issue in your original question.

To address the hacking, you need to carefully follow this guide. When you’re done, you may want to implement some (if not all) of the recommended security measures.