Vulnerability Discussion
Enforcing a minimum password lifetime helps to prevent repeated password changes to defeat the password reuse or history enforcement requirement. If users are allowed to immediately and continually change their password, then the password could be repeatedly changed in a short period of time to defeat the organization's policy regarding password reuse.
Check
Verify Ubuntu 22.04 LTS enforces a 24 hours/1 day minimum password lifetime for new user accounts by using the following command:
$ grep -i pass_min_days /etc/login.defs
PASS_MIN_DAYS 1
If "PASS_MIN_DAYS" is less than "1", is commented out, or is missing, this is a finding.
Fix
Configure Ubuntu 22.04 LTS to enforce a 24 hours/1 day minimum password lifetime.
Add or modify the following line in the "/etc/login.defs" file:
PASS_MIN_DAYS 1