Finally, here is a collection of actions you can take to make your Ubuntu 12.04 system more secure:
- Install Ubuntu 12.04 without connecting to the internet. This is to make sure that you do not download any upgrades during installation.
- After installation, login (without connecting to the internet) and remove zeitgeist and lenses
- Remove avahi-daemon
- Hide list of users on the Ubuntu login screen
- Remove rhythmbox completely from Ubuntu
- Remove guest login from the list of users on the login screen
- Check if your swap partition is encrypted
- You can now connect your system to the internet and restart.
- Make sure you keep your system packages up to date and apply any updates. Ubuntu also does this automatically.
- Add new users with encrypted home folders
- List all services connected to the internet
- Enable the Ubuntu firewall
- You can manage services/daemons using the command line or using bum.
- Retrieve the home folder encryption passphrase if you did not record it during installation or creation of new users
- Uninstall ubufox Firefox extension, if you do not need it.