Why this helps
SSH is a common entry point. Hardening defaults dramatically lowers brute-force and credential theft risk on exposed systems.
Step-by-step guide
Secure SSH defaults
Apply stronger SSH defaults and key-only access for remote machines.
How to verify
Run ssh -v login tests from a trusted host and confirm password logins fail while key logins succeed.
Steps
- Create SSH keys and confirm key login works.
- Disable password authentication in sshd_config.
- Restrict SSH access with firewall rules.
- Enable fail2ban or equivalent lockout policy.