Alternative Joomla vulnerable extensions list - or another look at Joomla Redirect component
Have you ever checked native Joomla redirect component?
Navigate to Components -> Redirect in backend: you will see most of your 404 pages and additionally tons of garbage created by spam and hack bots which try to access well-known unsecure scripts.
Now search for 'option=com_' and you will see unsecure links to Joomla components. It's rather interesting to observe the possible security leaks and methods used.
Actually that's a Joomla vulnerable extensions list! But be quite, having link here means that link doesn't work, so you are safe.
But be careful with using old versions of extensions listed here, in most cases the security hole can exist in old version and your site can be hacked.