The Ubuntu operating system must enforce password complexity by requiring that at least one lower-case character be used.

STIG ID: UBTU-20-010051 |  SRG: SRG-OS-000070-GPOS-00038 |  Severity: low |  CCI:  | Vulnerability Id: V-238222

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.

Check

Add or update the "/etc/security/pwquality.conf" file to contain the "lcredit" parameter:

lcredit=-1

Fix

Verify the Ubuntu operating system enforces password complexity by requiring that at least one lower-case character be used.

Determine if the field "lcredit" is set in the "/etc/security/pwquality.conf" file with the following command:

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

If the "lcredit" parameter is greater than "-1" or is commented out, this is a finding.