🔐 Linux SSH Hardening Audit

Automated SSH security audit script for Linux servers with compliance checks and remediation recommendations.

📋 Overview

This Bash script audits critical SSH security configurations on Linux systems to ensure proper hardening against unauthorized access. It checks common security misconfigurations and provides actionable recommendations.

✅ Security Checks

• PermitRootLogin - Verifies root login is disabled
• PasswordAuthentication - Ensures password-based auth is disabled
• PubkeyAuthentication - Confirms SSH key authentication is enabled
• SSH Port - Displays current SSH port configuration
• SSH Service Status - Checks if SSH daemon is running
• UFW Firewall - Validates firewall is active and configured

🚀 Usage

Run the Audit

chmod +x audit_ssh.sh
sudo ./audit_ssh.sh

Sample Output

======================================
     🔐 SSH Hardening Audit Report
======================================
[OK]   Root login is disabled (PermitRootLogin no).
[WARN] Password login is NOT clearly disabled.
[INFO] Recommendation: set PasswordAuthentication no
[OK]   Public key login is enabled.
[INFO] SSH is running on port: 22 (default)
[OK]   SSH service is running.
[OK]   UFW firewall is active.
======================================
     ✅ Audit finished successfully
======================================

🛠️ Remediation

If warnings are found, apply these fixes:

# Edit SSH config
sudo nano /etc/ssh/sshd_config

# Apply these settings:
PermitRootLogin no
PasswordAuthentication no
PubkeyAuthentication yes

# Restart SSH service
sudo systemctl restart sshd

# Enable UFW firewall
sudo ufw enable
sudo ufw allow 22/tcp

📦 Requirements

• Linux system (Ubuntu/Debian/RHEL/CentOS)
• SSH server installed
• Root/sudo access
• UFW (optional but recommended)

🎯 Use Cases

• Pre-deployment security audits
• Compliance verification
• Regular security assessments
• DevSecOps automation

📝 License

MIT