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.
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.
OL 8 uses "pwquality" as a mechanism to enforce password complexity. Note that in order to require numeric characters without degrading the minlen value, the credit value must be expressed as a negative number in "/etc/security/pwquality.conf".
Check
Verify the value for "dcredit" in "/etc/security/pwquality.conf" or "/etc/security/pwquality.conf.d/*.conf" files with the following command:
$ sudo grep -r dcredit /etc/security/pwquality.conf*
/etc/security/pwquality.conf:dcredit = -1
If the value of "dcredit" is a positive number or is commented out, this is a finding.
If conflicting results are returned, this is a finding.
Fix
Configure OL 8 to enforce password complexity by requiring that at least one numeric character be used by setting the "dcredit" option.
Add or update the following line in the "/etc/security/pwquality.conf" file or a configuration file in the "/etc/security/pwquality.conf.d/" directory:
dcredit = -1
Remove any configurations that conflict with the above value.