Unpatched XRING Flaw in XQUIC Lets Remote Clients Crash HTTP/3 Servers

Jul 10, 2026 - 14:00
Unpatched XRING Flaw in XQUIC Lets Remote Clients Crash HTTP/3 Servers
A single wrong variable on one line in XQUIC, Alibaba's QUIC and HTTP/3 library, lets any remote client crash the server with a short burst of completely legal traffic. There is no patch. FoxIO researcher Sébastien Féry disclosed the flaw on July 8 and nicknamed it XRING. He says it needs no login and no malformed packets: about 260 bytes of ordinary QPACK traffic takes the server