How Misconfigured Docker Ports Bypass Every Firewall You Set Up (opens in new tab)

Originally published at fatihsennik.com You were running your own servers. You thought you understood firewalls such as UFW rules, iptables, Cloudflare in front of everything. You'd done the reading. You knew what you were doing. Then you set up Docker on a new server and watched it silently undo all of it. This isn't a hypothetical. I found this the hard way, on a friend's server, after something was already listening on a port that had no business being open. How It Started The server was a...