{"id":"CVE-2026-78663","title":"The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered da…","summary":"The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered da…","severity":"none","published":"2026-10-08","updated":"2026-10-08","sourceUpdated":"2026-10-08T23:17:03.647","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-78663","references":[{"url":"https://go.dev/cl/847187","label":"security@golang.org"},{"url":"https://go.dev/cl/847310","label":"security@golang.org"},{"url":"https://go.dev/issue/81743","label":"security@golang.org"},{"url":"https://groups.google.com/g/golang-announce/c/U2fTuyDJznI","label":"security@golang.org"},{"url":"https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs","label":"security@golang.org"},{"url":"https://pkg.go.dev/vuln/GO-2026-6612","label":"security@golang.org"}],"tags":["nvd"],"ingestedAt":"2026-10-09T00:19:50.975Z","slug":"CVE-2026-78663","body":"## Overview\n\nThe HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}