Beginners guide to Lynis

Hello, aspiring ethical hackers. In this blogpost, you will learn about a tool called Lynis, the security auditing and hardening tool for UNIX based systems like Linux, macOS, BSD and others. It performs an in-depth security scan to test security defenses and provide suggestions for further system hardening.

This tool audits the following features on the system.

1. General system information.
2. System tools.
3. Operating system.
4. Boot and other services.
5. Kernel vulnerabilities.
6. Memory and processes.
7. Users, groups and authentication
8. Kerberos
9. Shells
10. File systems
11. USB devices
12. Storage
13. NFS
14. Name Services
15. Ports and packages
16. Networking
17. Printers and Spool
18. Email and messaging software
19. Firewalls
20. Web servers
21. SSH and SNMP
22. Databases
23. PHP (in web server)
24. Logging and log files
25. Insecure services
26. Banners
27. Scheduled Tasks
28. Accounting
29. Time and synchronization
30. Cryptography
31. Virtualization
32. Containers
33. Security frameworks
34. System tools and malware
35. File permissions etc.

Let’s see how to run Lynis for the first time. For this, we will be using Kali Linux. It can be installed on Kali as shown below.

After the installation is successful, run the command shown below to run it to audit the entire system.

lynis audit system

It runs as shown below.

While auditing, wherever there is scope for hardening, lynis adds a suggestion as shown below.

After the entire system is audited, Lynis provides summary of the entire audit as shown below.

Below the summary, you can find each suggestion as shown below.

You can harden your system based on these suggestions. You can also find this information in the log reports of Lynis.