RHEL 9 SSHD must accept public key authentication.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-257983	RHEL-09-255035	SV-257983r997068_rule		Medium

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 common access card (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 common access card (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

STIG	Date
Red Hat Enterprise Linux 9 Security Technical Implementation Guide	2024-06-04

Details

Check Text ( C-61724r952176_chk )
Verify that RHEL 9 SSH daemon accepts public key encryption with the following command: $ sudo /usr/sbin/sshd -dd 2>&1 \| awk '/filename/ {print $4}' \| tr -d '\r' \| tr '\n' ' ' \| xargs sudo grep -iH '^\s*pubkeyauthentication' PubkeyAuthentication yes If "PubkeyAuthentication" is set to no, the line is commented out, or the line is missing, this is a finding.

Fix Text (F-61648r925935_fix)
To configure the system add or modify 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