Linux hardening

This intensive 1‑day training teaches you how to harden a Linux server from the ground up. You’ll learn to minimize the system footprint, lock down user privileges, secure network exposure, and reinforce critical services. Through hands‑on exercises, you’ll apply real‑world hardening techniques used by security professionals.

Targeted audience:

• System administrators
• Dev(Sec)Ops engineers

Educational goals:

• Identify common entry points, privilege‑escalation paths, and misconfigurations
• Minimize installed software and apply kernel and filesystem protections
• Configure strong authentication, secure sudo policies, and controlled user environments
• Secure network interfaces, firewall rules, and remote access pathways
• Deploy logging, auditing, and basic intrusion‑detection mechanisms

Prerequisites:

• Being comfortable with CLI mode
• Familiarity with basic Linux administration

Program:

Introduction

• Why hardening matters?
• Understanding the attack surface
• Defense in depth
• Principle of least privilege

System & account hardening

• Partitioning strategy
• Account and sudo hardening
• Password and authentication policy
• Unnecessary packages & services
• Unused kernel modules

Network & access hardening

• SSH hardening
• Firewalling
• Brute-force mitigation

Filesystem, permissions & integrity

• SUID/SGID auditing
• Sticky bit and ACLs
• Immutable attributes
• File integrity monitoring

Logging, auditing & monitoring

• Kernel-level security event
• Centralized logging
• Intrusion detection concepts

Automation & compliance validation

• Scoring with Lynis
• Formal compliance scoring with OpenSCAP
• Hardening-as-code with Ansible

Resources

• Books
• Interactive platforms
• Courses & videos
• Tools

Gwendal Le Coguic - contact@glc.st - quotes on request - SIRET 79778302400038