The system must prohibit the reuse of passwords within five iterations.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-218026	RHEL-06-000274	SV-218026r505923_rule		Medium

Description
Preventing reuse of previous passwords helps ensure that a compromised password is not reused by a user.

STIG	Date
Red Hat Enterprise Linux 6 Security Technical Implementation Guide	2020-09-03

Details

Check Text ( C-19507r462403_chk )
To verify the password reuse setting is compliant, run the following command: # grep remember /etc/pam.d/system-auth /etc/pam.d/password-auth If the line is commented out, the line does not contain "password required pam_pwhistory.so" or "password requisite pam_pwhistory.so", or the value for "remember" is less than “5”, this is a finding.

Fix Text (F-19505r462404_fix)
Do not allow users to reuse recent passwords. This can be accomplished by using the "remember" option for the "pam_pwhistory" PAM module. In the file "/etc/pam.d/system-auth" and /etc/pam.d/password-auth, append "remember=5" to the lines that refer to the "pam_pwhistory.so" module, as shown: password required pam_pwhistory.so [existing_options] remember=5 or password requisite pam_pwhistory.so [existing_options] remember=5 The DoD requirement is five passwords.

Fix Text (F-19505r462404_fix)

Do not allow users to reuse recent passwords. This can be accomplished by using the "remember" option for the "pam_pwhistory" PAM module. In the file "/etc/pam.d/system-auth" and /etc/pam.d/password-auth, append "remember=5" to the lines that refer to the "pam_pwhistory.so" module, as shown:

password required pam_pwhistory.so [existing_options] remember=5

or

password requisite pam_pwhistory.so [existing_options] remember=5

The DoD requirement is five passwords.