Active Directory has a feature called Realm Trust, which allows AD to trust an external Kerberos realm for purposes of authentication.
So, does Auth0 offer a service that presents a Kerberos domain controller?
Or ,does Auth0 offer some other service that will get me to the same place, i.e. where AD will trust Auth0 (directly or indirectly) to authenticate a user?
I think the answer is no, and I think this is an unpopular scenario, but I had to ask.
To my knowledge there is no such support for the exact thing you’re looking for. In addition the only thing that I’m aware and that could remotely be of any relevance would be the support to configure Auth0 as the identity provider in a federation with Active Directory Federation Services (ADFS). However, technically this seems to differ as it would just be a way to have ADFS trust the service as an additional identity provider, however, this is at an higher level and not so much at the level of the directory itself. Nonetheless, I wanted to mention it in case it’s somewhat relevant.