Security Enhancement for WebSockets to Prevent Private Network Mapping
Tom Gallagher · 2016
This document proposes an update to RFC 6455 (WebSockets) which would enhance security by preventing network mapping via WebSockets. By comparing timing differences between failed opening handshakes, WebSockets can be abused within web browsers to discover details about a target's private network. WebSocket network mapping is more efficient than other in-browser mapping techniques as it can take advantage of child WebWorker processes to bypass the throttling mitigations in many browsers. An attacker can exploit this browser weakness when a victim accesses an attacker-controlled web page.