Implementing Operating System Hardening Techniques on a Linux Server (XK0-006)
This lab aligns to the following CompTIA Linux+ (XK0-006) exam objectives:
- 3.3: Given a scenario, apply operating system (OS) hardening techniques on a Linux system.
- 5.4: Given a scenario, analyze and troubleshoot security issues on a Linux system.
By the end of this lab, you will be able to:
- Configure privilege escalation controls and restrict wheel group membership on a Linux server.
- Apply file attributes to protect critical system files from unauthorized modification.
- Identify and remediate world-writable files and apply appropriate permission settings.
- Configure Access Control Lists (ACLs) to enforce granular file access policies.
- Harden SSH access and disable insecure services to reduce the system's attack surface.
Overview
Welcome to the Implementing Operating System Hardening Techniques on a Linux Server lab. In this lab, you will apply a series of structured hardening tasks to an AlmaLinux system to reduce its attack surface and strengthen overall security posture. You will begin with a reading assignment that introduces how file permissions, ownership, and advanced access controls such as SELinux work together to protect system resources and how misconfigurations can lead to security risks or service failures.
You will then apply these concepts in a hands-on environment by controlling privilege escalation through sudoers configuration, protecting system account files using file attributes, identifying and remediating insecure permissions, and applying ACLs for fine-grained access control. You will also harden SSH, disable insecure protocols, and prevent unused file systems from loading to reduce potential attack vectors.
By the end of this lab, you will be able to apply OS hardening practices, diagnose access-related issues, and configure secure systems consistent with real-world Linux administration standards.
You will complete the following two activities in this lab:
- Reading Assignment – Linux Security and Access Control
- Exercise 1 – Hardening a Linux Server Operating System
Click Next to continue.