The system must require passwords to contain at least one lower-case alphabetic character.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-50917	OL6-00-000059	SV-65123r3_rule		Low

Description
Requiring a minimum number of lowercase characters makes password guessing attacks more difficult by ensuring a larger search space.

STIG	Date
Oracle Linux 6 Security Technical Implementation Guide	2018-09-19

Details

Check Text ( C-53373r3_chk )
To check how many lower-case characters are required in a password, run the following command: $ grep pam_cracklib /etc/pam.d/system-auth /etc/pam.d/password-auth The "lcredit" parameter (as a negative number) will indicate how many lower-case characters are required. The DoD requires at least one lower-case character in a password. This would appear as "lcredit=-1". If the “lcredit” parameter is not found or not set to the required value, this is a finding.

Check Text ( C-53373r3_chk )

To check how many lower-case characters are required in a password, run the following command:

$ grep pam_cracklib /etc/pam.d/system-auth /etc/pam.d/password-auth

The "lcredit" parameter (as a negative number) will indicate how many lower-case characters are required. The DoD requires at least one lower-case character in a password. This would appear as "lcredit=-1".

If the “lcredit” parameter is not found or not set to the required value, this is a finding.

Fix Text (F-55713r3_fix)
The pam_cracklib module's "lcredit=" parameter controls requirements for usage of lower-case letters in a password. When set to a negative number, any password will be required to contain that many lower-case characters. Edit /etc/pam.d/system-auth and /etc/pam.d/password-auth adding "lcredit=-1" after pam_cracklib.so to require use of a lower-case character in passwords.