Information
The PASS_WARN_AGE parameter in /etc/login.defs allows an administrator to notify users that their password will expire in a defined number of days. It is recommended that the PASS_WARN_AGE parameter be set to 7 or more days.
Rationale:
Providing an advance warning that a password will be expiring gives users time to think of a secure password. Users caught unaware may choose a simple password or write it down where it may be discovered.
Solution
Set the PASS_WARN_AGE parameter to 7 in /etc/login.defs:
PASS_WARN_AGE 7
Modify user parameters for all users with a password set to match:
# chage --warndays 7 <user>
Additional Information:
You can also check this setting in /etc/shadow directly. The 6th field should be 7 or more for all users with a password.
Item Details
Category: CONFIGURATION MANAGEMENT, SYSTEM AND SERVICES ACQUISITION
References: 800-53|CM-2, 800-53|CM-6, 800-53|CM-7, 800-53|CM-7(1), 800-53|CM-9, 800-53|SA-3, 800-53|SA-8, 800-53|SA-10, CSCv6|16, CSCv7|4.4, CSCv7|16
Control ID: 184c86904b2fd0a5de2a7f1a892cfeb09c08b265f8ffdedad69f9e8627e54cc1