5.4.1.1 Ensure password expiration is 365 days or less - users

Information

The PASS_MAX_DAYS parameter in /etc/login.defs allows an administrator to force passwords to expire once they reach a defined age. It is recommended that the PASS_MAX_DAYS parameter be set to less than or equal to 365 days.

Rationale:

The window of opportunity for an attacker to leverage compromised credentials or successfully compromise credentials via an online brute force attack is limited by the age of the password. Therefore, reducing the maximum age of a password also reduces an attacker's window of opportunity.

Solution

Set the PASS_MAX_DAYS parameter to conform to site policy in /etc/login.defs :

PASS_MAX_DAYS 90

Modify user parameters for all users with a password set to match:

# chage --maxdays 90 <user>

Additional Information:

You can also check this setting in /etc/shadow directly. The 5th field should be 365 or less for all users with a password.

Note: A value of -1 will disable password expiration. Additionally the password expiration must be greater than the minimum days between password changes or users will be unable to change their password.

See Also

https://workbench.cisecurity.org/files/3399

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

Plugin: Unix

Control ID: 77a2db924c823b8560341d9f86d4cf115873945740264c0757be86ffe140256a