Impact If this library is used to implement a WebSocket server on top of a TCP server, by using the "WebSocket::Driver.server()" method, then a client can cause the server to crash by sending a "Host" header that is not a valid "host[:port]" string. When this happens, a "URI::InvalidURIError" exception is raised which is not caught, and this can cause the server process to crash if the application does not catch the error from the "parse()" method itself. Patches The issue has been patched in version 0.8.2 by making the request parser catch "URI::InvalidURIError" and enter an error state if the "Host" header is malformed. This means the request is considered invalid and should not establish a WebSocket connection. Workarounds No known workarounds exist. Acknowledgements This issue was discovered and reported by Pranjali Thakur, DepthFirst Security Research Team.