5.3.1 Ensure password creation requirements are configured - dcredit

Information

The pam_cracklib.so module checks the strength of passwords. It performs checks such as making sure a password is not a dictionary word, it is a certain length, contains a mix of characters (e.g. alphabet, numeric, other) and more. The following are definitions of the pam_cracklib.so options.

try_first_pass - retrieve the password from a previous stacked PAM module. If not available, then prompt the user for a password.
retry=3 - Allow 3 tries before sending back a failure.
minlen=14 - password must be 14 characters or more
dcredit=-1 - provide at least one digit
ucredit=-1 - provide at least one uppercase character
ocredit=-1 - provide at least one special character
lcredit=-1 - provide at least one lowercase character

The settings shown above are one possible policy. Alter these values to conform to your own organization's password policies.

Rationale:
Strong passwords protect systems from being hacked through brute force methods.

Solution

Edit the /etc/pam.d/common-password file to include the appropriate options for pam_cracklib.so and to conform to site policy:

password requisite pam_cracklib.so try_first_pass retry=3 minlen=14 dcredit=-1 ucredit=-1 ocredit=-1 lcredit=-1

See Also

https://workbench.cisecurity.org/files/1865

Item Details

Category: IDENTIFICATION AND AUTHENTICATION

References: 800-53|IA-5(1)(a)

Plugin: Unix

Control ID: eac73023bd06ec59c0faf756e6c0845d882707ee5601367185819dd731b72e5c