[terhechte]

If I understand it correctly, nginx in that gist refers to a binary that is not nginx and is only named so that it won't look suspicious in the process listing. apache httpd / nginx without CGI should be not vulnerable. However, if you use PHP or any other language and that performs some sort of system() call, there's a vulnerability.

[Pyppe]

That's what I initially figured, but was left uneasy after seeing the Gist and trying to Google about it.