It's currently running version 1.18.0, which is known to be remotely exploitable.

- http://www.shapeoko.com/wiki/index.php/Special:Version
- https://www.mediawiki.org/wiki/MediaWiki_1.18
Upgrading can be scripted to be near-automatic, if that helps, which really reduces the time and effort needed.
We used to run MediaWiki in a previous Community I was involved with, and upgrading (generally a monthly thing) wasn't a huge PITA.
It's mostly a case of untarring the latest release into the same webroot as the existing one, moving aside the files already there (excepting themes, uploads, and extensions).
If someone needs a hand with this stuff, I'm a decent *nix admin who can assist.
