Linux Security Guide

Expert-curated security practices, tools, and implementation strategies for robust Linux system protection

Foundational Linux Security Concepts

  • Understanding Linux Security Architecture
  • Discretionary Access Control (DAC)
  • Mandatory Access Control (MAC) - SELinux, AppArmor
  • User/Group Permissions & File System Security
  • Principle of Least Privilege Implementation
  • System Hardening Basics
  • Minimizing Attack Surface
  • Keeping Systems Updated (Patch Management)

User & Access Management

  • Strong Password Policies & MFA Implementation
  • SSH Hardening: Key-based Auth, Disable Root Login
  • Role-Based Access Control (RBAC)
  • Fail2ban Configuration & Account Lockout Policies
  • User Account Security
  • Group Management

File System Security

  • File Permissions and Ownership (chmod, chown)
  • Access Control Lists (ACLs)
  • File Integrity Monitoring
  • Full Disk Encryption (LUKS)
  • File-Level Encryption

Network Security

  • Firewall Management (iptables/nftables)
  • Network Segmentation
  • Network Monitoring (IDS/IPS)
  • Secure Network Protocols (SSH, TLS/SSL, VPNs)

Security Auditing & Monitoring

  • System Logging (/var/log)
  • Log Analysis Tools
  • Security Auditing Tools (Lynis, Auditd)
  • Vulnerability Scanning (OpenVAS, Nessus Essentials)

Malware & Threat Protection

  • Antivirus Software (ClamAV)
  • Rootkit Detection
  • Understanding Common Linux Threats

Advanced Security Topics

  • Kernel Security (Hardening, Modules)
  • Container Security (Docker/Kubernetes)
  • Security-Enhanced Linux (SELinux)
  • AppArmor

Security Best Practices & Policies

  • Security Policy Development
  • Incident Response Planning
  • Regular Security Audits
  • Backup and Recovery

Security Resources

Essential Security Tools

Learning Materials