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Servers – Ensure SSH Protocol is Set to 2
Support > Fixing Checks > Server
06 March, 2026
This check ensures that SSH Protocol version 2 is enabled for secure communication.
Older SSH versions (Protocol 1) have known security vulnerabilities. Enforcing Protocol 2 ensures stronger encryption and better protection against attacks.
Check Details
- Resource: Server
- Check: Ensure SSH Protocol is set to 2
- Risk: Using SSH Protocol 1 can expose the system to security vulnerabilities and potential attacks.
Remediation Steps
- Open a terminal session on the server with root or sudo privileges.
-
Open the SSH configuration file:
sudo nano /etc/ssh/sshd_config
-
Add or modify the following line to enforce SSH Protocol 2:
Protocol 2
- Save the file and exit the editor.
-
Restart the SSH service to apply the changes:
sudo systemctl restart sshd
-
Verify the configuration:
grep ^Protocol /etc/ssh/sshd_config
-
Ensure the output shows:
Protocol 2
- Perform regular audits to ensure the configuration remains compliant.