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.

Check

Verify Ubuntu 22.04 LTS enforces password complexity rules by using the following command:

$ grep -i enforcing /etc/security/pwquality.conf
enforcing = 1

If "enforcing" is not "1", is commented out, or is missing, this is a finding.

Check for the use of "pwquality" by using the following command:

$ cat /etc/pam.d/common-password | grep requisite | grep pam_pwquality
password requisite pam_pwquality.so retry=3

If "retry" is set to "0" or is greater than "3", or is missing, this is a finding.

Fix

Configure Ubuntu 22.04 LTS to enforce password complexity rules.

Add or modify the following line in the "/etc/security/pwquality.conf" file:

enforcing = 1

Add or modify the following line in the "/etc/pam.d/common-password" file:

password requisite pam_pwquality.so retry=3

Note: The value of "retry" should be between "1" and "3".