Docker bridge network private IP's visible on external network interface

I’m running Community Edition Docker version 19.03.2, build 6a30dfc on Ubuntu server 18.04 on a VMWare ESX host.

The problem is that on VMcenter, I can see the internal IP’s of private bridge networks (see screenshots).

There’s concerns from our network administrators that this may be broadcasting traffic and may cause some conflicts. Hence I want them to be completely isolated. My understanding is that all the docker created networks are bridge networks sitting behind a NAT so I’m not sure why the private internal IP’s are visible externally.

How can I make sure that docker internal virtual bridge networks IP are not exposed and are completed hidden from the external network but are able to access services on the external network via only the IP of the host?