Ubuntu 24.04 LTS must not allow accounts configured in Pluggable Authentication Modules (PAM) with blank or null passwords.

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
highV-270714SRG-OS-000480-GPOS-00227UBTU-24-300028SV-270714r1067119_rule2025-02-181
Description
If an account has an empty password, anyone could log on and run commands with the privileges of that account. Accounts with empty passwords must never be used in operational environments.
ℹ️ Check
To verify null passwords cannot be used, run the following command: $ grep nullok /etc/pam.d/common-password If this produces any output, this is a finding.
✔️ Fix
If an account is configured for password authentication but does not have an assigned password, it is possible to log on to the account without authenticating. Remove any instances of the "nullok" option in "/etc/pam.d/common-password" to prevent logons with empty passwords.