Lynis is a security auditing tool for systems based on UNIX, like Linux, macOS, BSD, and others. It performs an in-depth security scan and runs on the system itself. The primary goal is to test security defenses and provide tips for further system hardening. It will also scan for general system information, vulnerable software packages, and possible configuration issues. System administrators and auditors commonly used Lynis to assess the security defenses of their systems. Besides the "blue team," nowadays, penetration testers also have Lynis in their toolkit.
We believe software should be simple, updated regularly, and open. You should be able to trust, understand, and have the option to change the software. Many agree with us, as the software is being used by thousands every day to protect their systems.
Source code and additional information can be found here: https://github.com/CISOfy/Lynis