src/de/steamwar/bungeecore/comms/SpigotReceiver.java

@@ -37,8 +37,10 @@ public class SpigotReceiver extends BasicListener {
     public void onPluginMessage(PluginMessageEvent event) {
         if(!event.getTag().equalsIgnoreCase("sw:bridge"))
             return;
-        if(!event.getSender().getAddress().getHostName().equals("localhost"))
+        if(!event.getSender().getAddress().getHostName().equals("localhost")){
+            event.setCancelled(true);
             return;
+        }
         ByteArrayDataInput in = ByteStreams.newDataInput(event.getData());
         Byte handler = in.readByte();
         handlerMap.get(handler).handle(in);