Joomla! Documentation™

When you operate a dedicated or VPS server as a webhost or reseller with root access, you might want to find outdated Joomla versions that could jeopardize the security of your server. If you have unlimited root access, use this command to find the Joomla version for each user:

find /home/*/public_html/ -type f \( -iwholename '*/libraries/joomla/version.php' -o -iwholename '*/libraries/cms/version.php' -o -iwholename '*/libraries/cms/version/version.php' \) -print -exec perl -e 'while (<>) { $release = $1 if m/RELEASE\s+= .([\d.]+).;/; $dev = $1 if m/DEV_LEVEL\s+= .(\d+).;/; } print qq($release.$dev\n);' {} \; && echo "-"

The output will list all user accounts with their Joomla version.

See Also

How to find outdated Joomla versions on your server to reduce the risk of being hacked