Free Hardening audit: Audit Linux, Nginx and PostgreSQL configs against CIS-style checks and fix them.

A configuration hardening audit in your browser, in the spirit of CIS-CAT, Lynis and OpenSCAP. Over 100 CIS-style checks for a Linux server (SSH, kernel network parameters, mounts, accounts and passwords, sudo, auditd, file permissions, services), Nginx (TLS versions and ciphers, security headers, server settings) and PostgreSQL (TLS, password hashing, logging, pg_hba.conf). Each finding shows the file and line, why it matters and the exact fix; many can be fixed with one click, and the score updates as you edit. Comes with three demo-bank servers to harden, or paste your own config files.

Free, no login, nothing to install. Your work stays in this browser.

What you can do

• Audit sshd_config, sysctl, fstab, sudoers, auditd rules and more
• Check Nginx TLS, ciphers and security headers (including add_header inheritance)
• Check PostgreSQL TLS, SCRAM passwords, logging and pg_hba.conf
• Fix findings in the editor or with one click, and export a CSV report

Graded, AI-assisted versions live in Linux administration, server hardening and security operations courses.