Because we use Linux, why shouldn't we care about security ?
There is a program generating a report on your Linux system security, it's called Lynis.
To instal it on Ubuntu (and derivatives), write:
$ sudo apt-get install lynis
Then, to launch it:
$ sudo lynis -c
You will have to type on <RETURN> key many times to validate each section. Eventually, you get an audit report with Warnings and Suggestions.
The report is accessible from /var/log/lynis.log (and you may grep it).
In the end, there's nothing really out of the ordinary, but it could be useful. A shame, in Ubuntu 14.04, it's still not the latest version that's been packaged !
Happy security audit ! !