Follow the principle of least privilege to limit what users and services can do.
Linux server hardening is the process of reducing a system's attack surface to protect against unauthorized access and data breaches. A default Linux installation is often a "blank canvas" rather than a fortress; hardening provides the necessary reinforcement.
The most critical step is ensuring all software is current to close known vulnerabilities. Linux Server Hardening
Run system updates immediately upon setup (e.g., apt update && apt upgrade for Debian/Ubuntu or dnf update for RHEL/Fedora).
Securing the primary remote entry point is vital for stopping automated brute-force attacks. Follow the principle of least privilege to limit
Prevent direct root access by setting PermitRootLogin no in /etc/ssh/sshd_config .
Below is a structured write-up covering the essential stages of a Linux hardening project. 1. Update and Patch Management The most critical step is ensuring all software
Disable password-based authentication ( PasswordAuthentication no ) in favor of SSH key-pair authentication .