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

ucredit=-1

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:

ucredit=-1