IT Best Practices Tip: nist_V-38615
Severity: medium
Short Description
The SSH daemon must be configured with the Department of Defense (DoD) login banner.
Long Description
The warning message reinforces policy awareness during the logon process and facilitates possible legal action against attackers. Alternatively, systems whose ownership should not be obvious should ensure usage of a banner that does not provide easy attribution.
How to Check Correct Configuration
To determine how the SSH daemon's "Banner" option is set, run the following command:
# grep -i Banner /etc/ssh/sshd_config
If a line indicating /etc/issue is returned, then the required value is set.
If the required value is not set, this is a finding.
How to Fix
To enable the warning banner and ensure it is consistent across the system, add or correct the following line in "/etc/ssh/sshd_config":
Banner /etc/issue
Another section contains information on how to create an appropriate system-wide warning banner.