OL 9 SSHD must accept public key authentication.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-271721	SRG-OS-000105-GPOS-00052	OL09-00-002359	SV-271721r1091875_rule	2025-05-08	1

Description
Without the use of multifactor authentication, the ease of access to privileged functions is greatly increased. Multifactor authentication requires using two or more factors to achieve authentication. A privileged account is defined as an information system account with authorizations of a privileged user. A DOD CAC with DOD-approved PKI is an example of multifactor authentication. Satisfies: SRG-OS-000105-GPOS-00052, SRG-OS-000106-GPOS-00053, SRG-OS-000107-GPOS-00054, SRG-OS-000108-GPOS-00055

Description

Without the use of multifactor authentication, the ease of access to privileged functions is greatly increased. Multifactor authentication requires using two or more factors to achieve authentication. A privileged account is defined as an information system account with authorizations of a privileged user. A DOD CAC with DOD-approved PKI is an example of multifactor authentication. Satisfies: SRG-OS-000105-GPOS-00052, SRG-OS-000106-GPOS-00053, SRG-OS-000107-GPOS-00054, SRG-OS-000108-GPOS-00055

ℹ️ Check
Verify that OL 9 SSH daemon accepts public key encryption with the following command: $ sudo grep -i PubkeyAuthentication /etc/ssh/sshd_config PubkeyAuthentication yes If "PubkeyAuthentication" is set to no, the line is commented out, or the line is missing, this is a finding.

✔️ Fix
Configure OL 9 to accept public key authentication by adding or modifying the following line in "/etc/ssh/sshd_config". PubkeyAuthentication yes Restart the SSH daemon for the settings to take effect: $ sudo systemctl restart sshd.service