Prevent third party authentication from creating new users

We use Zammad as our ticketing system, and only want to allow staff users to log in to Zammad.

Currently, this works well using LDAP authentication, and disabling the web user creation.

We can enable third party sign on for Google by restricting it within Google to only our domain. However other third party authentication providers do not have this ability.

We are looking for an option to disable user creation from third party authentication all together, or for a way to link the accounts on first login with a new provider, if this is possible.

Thank you for all of the great work you have done on Zammad!

Sorry this is not possible.
Please note that this can’t be changed (at least in terms of automatic creation), because Zammad does also create new users if you receive a mail from an unknown user.

So this will hardly work for you.