RHEL 9 must be configured in the system-auth file to prohibit password reuse for a minimum of five generations.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-258093	RHEL-09-611020	SV-258093r926266_rule		Medium

Description
Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. If the information system or application allows the user to reuse their password consecutively when that password has exceeded its defined lifetime, the end result is a password that is not changed per policy requirements. RHEL 9 uses "pwhistory" consecutively as a mechanism to prohibit password reuse. This is set in both: /etc/pam.d/password-auth /etc/pam.d/system-auth Note that manual changes to the listed files may be overwritten by the "authselect" program.

Description

Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. If the information system or application allows the user to reuse their password consecutively when that password has exceeded its defined lifetime, the end result is a password that is not changed per policy requirements. RHEL 9 uses "pwhistory" consecutively as a mechanism to prohibit password reuse. This is set in both: /etc/pam.d/password-auth /etc/pam.d/system-auth Note that manual changes to the listed files may be overwritten by the "authselect" program.

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

Details

Check Text ( C-61834r926264_chk )
Verify RHEL 9 is configured in the system-auth file to prohibit password reuse for a minimum of five generations with the following command: $ grep -i remember /etc/pam.d/system-auth password required pam_pwhistory.so use_authtok remember=5 retry=3 If the line containing "pam_pwhistory.so" does not have the "remember" module argument set, is commented out, or the value of the "remember" module argument is set to less than "5", this is a finding.

Check Text ( C-61834r926264_chk )

Verify RHEL 9 is configured in the system-auth file to prohibit password reuse for a minimum of five generations with the following command:

$ grep -i remember /etc/pam.d/system-auth

password required pam_pwhistory.so use_authtok remember=5 retry=3

If the line containing "pam_pwhistory.so" does not have the "remember" module argument set, is commented out, or the value of the "remember" module argument is set to less than "5", this is a finding.

Fix Text (F-61758r926265_fix)
Configure the RHEL 9 system-auth file to prohibit password reuse for a minimum of five generations. Add the following line in "/etc/pam.d/system-auth" (or modify the line to have the required value): password required pam_pwhistory.so use_authtok remember=5 retry=3