When you're managing Joomla sites it's reasonably easy to keep track of updates, especially if you use something like Watchful to help you. When you're running a server and only managing some (or none) of those sites, it becomes a little more difficult (especially on a busy shared hosting server).
It's quite easy to shrug and say 'Not my site, not my problem', but the simple fact is that it is. The second someone manages to compromise one of the sites you host, they're going to try and find a way to run arbitrary code, once they've done that they'll try to run an auto-rooter. If they succeed, it's game over for everyone you host!
The extension that always comes to mind, is the Joomla Content Editor (JCE) as they had a nasty vulnerability involving spoofed GIFs some time back. You'd hope that everyone would have updated by now, but there still seem to be a lot of sites running versions older than 2.1.1!
In this post, we'll be creating a script designed to automatically check every one of the sites you host for a version of JCE older than the latest. Adjusting it to check other extensions is easy, so long as that extension has an update stream.