I have KDE installed with lightdm greeter/login. I have a Linux workstation set up as an Active Directory domain member. I can log in as an AD domain user using the domain PW.

As an experiment, I tried using the KDE desktop's Application Launcher > System Settings > Account Details > Change Password, to change this user's password. Big problem! It changed the password, but only on the local workstation. It did not change the user's domain password. This user can now no longer authenticate with the domain, but must log into this workstation with the changed password.

I need to know where either lightdm or KDE (not sure which) stores these credentials so I can purge them.

Does anyone know?