Brief Description

It can cause a severe DoS attack that prevents clients from connecting to the NetherNet server.

Steps to Reproduce

1. Start BDS with NetherNet.

2. Send a large number of /v1/join/{networkId} requests to the specified TCP port of BDS.

3. All UDP listening ports in the specified range are reserved.

4. The entire range is exhausted, preventing new clients from connecting.

Expected Behavior

UDP ports are released when they are exhausted or when time passes without use, so acceptance is not blocked.

Actual Behavior

Available ports run out, resulting in no candidate lines present in the SDP offer response from the server, and the client cannot proceed any further with the connection process.

Suggested Fix

This is a personal idea and just for reference, but I think it would be good to add a timeout argument to server.properties that releases UDP ports that have had no communication for a certain period of time, or to allow a single UDP port to accept multiple WebRTC connections.