When I create a user with
CREATE ROLE user123 LOGIN on my system it is able to login and immediately perform
\du and interact with pg_stat_activity, and probably many other things.
I have programmatically connecting software that should be performing a specific task. I don't want it to be able to do anything else, including spying on the connections, userIDs, user permissions or other things.
How do I prevent all unspecified access?