{"schema_version":"1.3.1","id":"GO-2026-6089","modified":"2026-08-13T21:43:54Z","published":"2026-08-13T21:43:54Z","aliases":["CVE-2026-56853"],"summary":"Apply ReadHeaderTimeout when doing unencrypted HTTP/2 check in net/http","details":"When a server is configured to support unencrypted HTTP/2, it reads a few bytes from each new connection to see if they contain the HTTP/2 client preface. ReadHeaderTimeout is unexpectedly not being applied when doing this.","affected":[{"package":{"name":"stdlib","ecosystem":"Go"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.25.13"},{"introduced":"1.26.0-0"},{"fixed":"1.26.6"},{"introduced":"1.27.0-0"},{"fixed":"1.27.0-rc.3"}]}],"ecosystem_specific":{"imports":[{"path":"net/http","symbols":["ListenAndServe","ListenAndServeTLS","Serve","ServeTLS","Server.ListenAndServe","Server.ListenAndServeTLS","Server.Serve","Server.ServeTLS","conn.readRequest","conn.serve"]}]}}],"references":[{"type":"REPORT","url":"https://go.dev/issue/80205"},{"type":"FIX","url":"https://go.dev/cl/795540"},{"type":"WEB","url":"https://groups.google.com/g/golang-announce/c/94pEornpRlI"}],"database_specific":{"url":"https://pkg.go.dev/vuln/GO-2026-6089","review_status":"REVIEWED"}}