CVE-2026-54465websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.8.1, when websocket-driver is used to implement a WebSocket server on top of a TCP server using WebSocket:
river.server() or to complement a WebSocket client, a peer can make a single connection consume an unbounded amount of memory by sending an HTTP request or response with a never-ending list of headers. This can lead to the receiving process running out of memory. This issue is fixed in version 0.8.1.