5.4.3 Ensure password reuse is limited

Information

The /etc/security/opasswd file stores the users' old passwords and can be checked to ensure that users are not recycling recent passwords.

Notes:

Additional module options may be set, recommendation only covers those listed here.

This setting only applies to local accounts.

This option is configured with the remember=n module option in /etc/pam.d/common-password

Rationale:

Forcing users not to reuse their past passwords make it less likely that an attacker will be able to guess the password.

Solution

Run the following command:

# pam-config -a --pwhistory --pwhistory-remember=5

OR
Edit the file /etc/pam.d/common-password to include the remember= option and conform to site policy as shown:

password required pam_pwhistory.so remember=5

See Also

https://workbench.cisecurity.org/files/3288