Random Player joins my sessions on purposely crashes the game

A grief-er seems to be able to join random players game and crash the clients.

Here is a video clip of how a random guy joins my game and then proceeds to cause destruction and destroy things until the game crashes out.


Lucky for us today's patch notes includes a fix for this exact issue.

Patch notes for version 0.2.115.0:

• Ensure that players joining a Steam MP session are friends with someone currently in session.