SEP (Symantec Endpoint Protection) for Mac is displaying "Norton Security" popups for application traffic.
Various "Norton Security" popups asking whether to block or allow traffic to various applications on the Mac
These notices are for an application control feature that is not yet implemented and there are no related user-configurable settings in SEP. This traffic should automatically be allowed and governed by SEP firewall settings.
Symantec/Broadcom is aware of this issue and will updated this article as new information becomes available.