Yep. It had to add a Dockerfile to build MediaWiki using vulnerable versions but it's that, a compose file, and a Python file. To be clear it still has a lot of the limitations of the other POCs, but it does work.
Yes, it was actually using php2shell. Not a mediawiki vulnerability. It was the easier and less resilient variant of php2shell, but still a real POC. I'm confident that it could also do Wordpress if tasked to.
