Used to evaluate the security defenses of Linux/Unix-based systems. It runs on the host itself, so it performs more extensive security scans than vulnerability scanners.
Lynis runs on almost all Unix-based systems and versions, including:
Lynis is flexible and easy to use. Installation is optional. Just copy it to a system, and use "./lynis audit system" to start the security scan. It is written in shell script and released as open source software (GPL).