Vulnerability Discussion
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. If RHEL 9 allows the user to select passwords based on dictionary words, this increases the chances of password compromise by increasing the opportunity for successful guesses, and brute-force attacks.
Check
Verify RHEL 9 prevents the use of dictionary words for passwords with the following command:
$ sudo grep dictcheck /etc/security/pwquality.conf /etc/pwquality.conf.d/*.conf
/etc/security/pwquality.conf:dictcheck=1
If "dictcheck" does not have a value other than "0", or is commented out, this is a finding.
Fix
Configure RHEL 9 to prevent the use of dictionary words for passwords.
Add or update the following line in the "/etc/security/pwquality.conf" file or a configuration file in the /etc/pwquality.conf.d/ directory to contain the "dictcheck" parameter:
dictcheck=1