STIG ID: RHEL-09-611110 | SRG: SRG-OS-000069-GPOS-00037 | Severity: medium | CCI: | Vulnerability Id: V-258111
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised. Requiring a minimum number of uppercase characters makes password guessing attacks more difficult by ensuring a larger search space.
Configure RHEL 9 to enforce password complexity by requiring that at least one uppercase character be used by setting the "ucredit" option.
Add the following line to /etc/security/pwquality.conf (or modify the line to have the required value):
ucredit = -1
Verify that RHEL 9 enforces password complexity by requiring that at least one uppercase character.
Check the value for "ucredit" with the following command:
$ sudo grep ucredit /etc/security/pwquality.conf /etc/security/pwquality.conf/*.conf
ucredit = -1
If the value of "ucredit" is a positive number or is commented out, this is a finding.