5.1.4 Ensure SSH Protocol is set to 2

Information

Older versions of SSH support two different and incompatible protocols: SSH1 and SSH2. SSH1 was the original protocol and was subject to security issues. SSH2 is more advanced and secure.

Rationale:

SSH v1 suffers from insecurities that do not affect SSH v2.

Solution

Edit the /etc/ssh/sshd_config file to set the parameter as follows:

Protocol 2

Additional Information:

This command not longer exists in newer versions of SSH. This check is still being included for systems that may be running an older version of SSH. As of openSSH version 7.4 this parameter will not cause an issue when included.

See Also

https://workbench.cisecurity.org/files/3659

Item Details

Category: ACCESS CONTROL, CONFIGURATION MANAGEMENT, IDENTIFICATION AND AUTHENTICATION, MAINTENANCE, SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|AC-17(2), 800-53|CM-7, 800-53|IA-5, 800-53|IA-5(1), 800-53|MA-4, 800-53|SC-8, 800-53|SC-8(1), CSCv7|4.5, CSCv7|14.4

Plugin: Unix

Control ID: 2062c0dbb2e43c5e868ef42aeb04938c61fddbc64a4544023edfc66518e4b9ae