It is not possible to share an interface with people who are not collaborators in the base. (If you share an interface with someone who is not a collaborator in the base, the person is made a collaborator in the base.)
Anyone who is a collaborator on the base can share the base. You cannot prevent other users from sharing the base without your knowledge.
This is a real issue.
We should be able to use interface and give specific access, that’s the whole point of interface. Not giving access to the whole base but just specific tabs and records to be completed. When will this be available?