Context: I'm running a home game server and my paranoid network administrator has allowed port forwarding under the sole condition that I airgap the server hardware when I'm not actively using it. Our router system has been configured for port forwarding to the server.

Is there a protocol for how routers respond when they can't find the port to forward to? Can Eve the hacker determine that there is a possible vulnerability by analyzing that there's a different response from the port than from all the others?

  • What your router does or doesn't do in that case depends on its firmware and its configuration. A reasonable way to handle these situations is to put the server in a partitioned VLAN, a DMZ. Home networking is off-topic here however. – Zac67 Feb 28 at 7:13