Hi,
I'm a long-time Linux sysadmin but haven't done much with docker and containers or firewalls beyond iptables. I have inherited a fedora38 system where another admin has installed python3-docker, but port 8080 is now exposed to the Internet.

I have a basic iptables firewall that I set up some time ago (when the system was probably fedora35), but iptables also shows some docker rules:

# iptables -nvL|grep ^Chain|grep DOCKER
Chain DOCKER (2 references)
Chain DOCKER-ISOLATION-STAGE-1 (1 references)
Chain DOCKER-ISOLATION-STAGE-2 (2 references)

Where do these chains/policies come from? Is it also an iptables firewall or is it using ufw? 

Why wouldn't it use firewall-cmd? Isn't that the default desktop firewall app now for fedora?