Enforcement of Password Complexity
The Ubuntu operating system must enforce password complexity by requiring that at least one upper-case character be used.
Rationale: 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.
Audit: Verify the Ubuntu operating system enforces password complexity by requiring that at least one upper-case character be used.
Determine if the field ucredit is set in the /etc/security/pwquality.conf file with the following command:
grep -i “ucredit” /etc/security/pwquality.conf
If the “ucredit” parameter is greater than “-1”, or is commented out, this is a finding.
Remediation: Add or update the /etc/security/pwquality.conf file to contain the ucredit parameter: