9
Here is what i would do:
1. remove all un-needed modules. Specially all modules that have possibility to add some content (like: fileupload modules, gallery etc)
2. Walk throuh your files+folders and do a proper chmod
3. Read all you logfiles (httpd, xoops) frequently
4. Search for Any exploit´s on your os/software/modules/system/etc and be a step before any intruders
5. Password checks (remove accounts with short passwords)
6. If you host the system: check your firewall rules/logs
7. If you host the system: Add a security module to apache - here is a nice one:
http://www.modsecurity.org/8. Add .htaccess files to prevent access to special folders.
9. If you host the system: Block IP-adresses in youre firewall
10. If you host the system: Remove un-needed services and only accept http-trafic to the system.
11. setup a honey-trap and collect evidence/logs
And remember....they will read this to...