When I started working with my bosses (3 months ago) they had a couple of sites that have an old version of Joomla. Not being familiar with Joomla (I do Wordpress sites), I didn't realize the danger.

I recently moved the two sites to new hosting (the old host company was insistent we had to move them off - now I think I understand why). the one site which has a version 1.5.22 on Joomla, was injected with a perl script just before Christmas and again on the 9th of January 2014. I...