RHEL 9 must enable the Pluggable Authentication Module (PAM) interface for SSHD.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-257986	RHEL-09-255050	SV-257986r943038_rule		High

Description
When UsePAM is set to "yes", PAM runs through account and session types properly. This is important when restricted access to services based off of IP, time, or other factors of the account is needed. Additionally, this ensures users can inherit certain environment variables on login or disallow access to the server.

STIG	Date
Red Hat Enterprise Linux 9 Security Technical Implementation Guide	2023-12-01

Details

Check Text ( C-61727r943037_chk )
Verify the RHEL 9 SSHD is configured to allow for the UsePAM interface with the following command: $ sudo grep -ir usepam /etc/ssh/sshd_config /etc/ssh/sshd_config.d/* UsePAM yes If the "UsePAM" keyword is set to "no", is missing, or is commented out, this is a finding.

Fix Text (F-61651r925944_fix)
Configure the RHEL 9 SSHD to use the UsePAM interface add or modify the following line in "/etc/ssh/sshd_config". UsePAM yes Restart the SSH daemon for the settings to take effect: $ sudo systemctl restart sshd.service