PLAYING WITH HTTP/2 CONNECT

Summary from the TLDR InfoSec newsletter

HTTP/2 CONNECT is an upgrade over the original HTTP/1 CONNECT method, shifting from tunneling entire TCP connections to multiplexing multiple streams within a single connection. This evolution enables more efficient proxying and port scanning by allowing numerous tunnels without the overhead of opening many separate TCP sessions. The protocol's design incorporates features like HPACK header compression and support for modern proxy use cases—including WebSocket, UDP, and raw IP proxying—making it highly relevant for security research and next-generation proxy infrastructure.