# CIS 5.4.1.2 Ensure minimum days between password changes is 7 or more (Scored) # # Description # =========== # The PASS_MIN_DAYS parameter in /etc/login.defs allows an administrator to # prevent users from changing their password until a minimum number of days # have passed since the last time the user changed their password. It is # recommended that PASS_MIN_DAYS parameter be set to 7 or more days. # # Rationale # ========= # By restricting the frequency of password changes, an administrator can # prevent users from repeatedly changing their password in an attempt to # circumvent password reuse controls. # # Audit # ===== # Run the following command and verify PASS_MIN_DAYS is 7 or more: # # # grep PASS_MIN_DAYS /etc/login.defs # PASS_MIN_DAYS 7 # # Verify all users with a password have their minimum days between password # change set to 7 or more: # # # egrep ^[^:]+:[^\!*] /etc/shadow | cut -d: -f1 # # # chage --list # Minimum number of days between password change: 7 # # Remediation # =========== # Set the PASS_MIN_DAYS parameter to 7 in /etc/login.defs : # # PASS_MIN_DAYS 7 # # Modify user parameters for all users with a password set to match: # # # chage --mindays 7 # # Notes # ===== # You can also check this setting in /etc/shadow directly. The 5th field # should be 7 or more for all users with a password. # parameters: linux: system: login_defs: PASS_MIN_DAYS: value: 7