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. "pwquality" enforces complex password construction configuration and has the ability to limit brute-force attacks on the system.

RHEL 8 uses "pwquality" as a mechanism to enforce password complexity. This is set in both:
/etc/pam.d/password-auth
/etc/pam.d/system-auth

Check

Verify the operating system uses "pwquality" to enforce the password complexity rules.

Check for the use of "pwquality" in the system-auth file with the following command:

$ sudo cat /etc/pam.d/system-auth | grep pam_pwquality

password requisite pam_pwquality.so

If the command does not return a line containing the value "pam_pwquality.so" as shown, or the line is commented out, this is a finding.

Fix

Configure the operating system to use "pwquality" to enforce password complexity rules.

Add the following line to the "/etc/pam.d/system-auth" file (or modify the line to have the required value):

password requisite pam_pwquality.so