HTTP/2 & QUIC: Good Protocols, Bad Uses 🚨

by Catherine (Kate) Pearce & Carl Vincent

The meteoric rise of SPDY, HTTP/2, and QUIC has gone largely unremarked upon by most of the security field. QUIC is an application-layer UDP-based protocol that multiplexes connections between endpoints at the application level, rather than the kernel level. HTTP/2 (H2) is a successor to SPDY, and multiplexes different HTTP streams within a single connection. More than 10% of the top 1 Million websites are already using some of these technologies, including much of the 10 highest traffic sites. Whether you multiplex out across connections with QUIC, or multiplex into fewer connections with HTTP/2, the world has changed. We have a strong sensation of Déjà vu with this work and our 2014 BlackHat USA MPTCP research. We find ourselves discussing a similar situation in new protocols with technology stacks evolving faster than ever before, and Network Security is largely unaware of the peril already upon it. This talk briefly introduces QUIC and HTTP/2, covers multiplexing attacks beyond MPTCP, discusses how you can use these techniques over QUIC and within HTTP/2, and discusses how to make sense of and defend against H2/QUIC traffic on your network. We will also demonstrate, and release, some tools with these techniques incorporated.