I've previously used a great script on a Linux servers to report on all sorts of security issues.
It generates a comprehensive list of potential security flaws on the machine including:
- out of date software / bugs
- open ports
- incorrect privileges
And it summarises everything in a report along with suggested fixes.
Problem is I cann't remember the name of the script or where to find it?
Any clues?! J
chkrootkit and rkhunter are excellent choices, both being just shell scripts.
Then there are other security tools, such as Nessus , Prelude, tripwire and aide.
Maybe you are talking about Lynis, which is a security and system auditing tool. Tiger is a similar tool.
There is also Bastille Unix that lets you harden as you analyze.
EDIT: If it is none of the above, maybe is one of these other three (less known).