Joomla 1.5 is has now been out of support for some time. However, many sites are still running this version of the CMS. While it is tempting to just think "Well, the site is still working, so let's ignore this for now", there are now many known vulnerabilities in this version of Joomla. It is likely only a matter of time until a Joomla 1.5 site is compromised. Then the problem suddenly becomes urgent. We look at the process of upgrading.