{"action":"Upgrade stdlib to 1.26.9 or later.","affected":[{"fixed":"1.26.9","introduced":"0"},{"fixed":"1.27.2","introduced":"1.27.0-0"}],"component":"stdlib","cve_ids":["CVE-2026-56866"],"ecosystem":"Go","epss":0.00473,"exploited":false,"fixed_versions":["1.26.9","1.27.2"],"id":"tcs_01M5JHH8TRRVG73CQ4EZ6FGCCD","modified_at":"2026-10-16T09:55:59.367370212Z","published_at":"2026-10-08T22:31:09Z","references":["https://osv.dev/vulnerability/GO-2026-6605","https://go.dev/cl/847306","https://go.dev/issue/81740","https://groups.google.com/g/golang-announce/c/U2fTuyDJznI"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"GO-2026-6605","url":"https://osv.dev/vulnerability/GO-2026-6605"},{"source":"nvd","source_id":"CVE-2026-56866","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56866"}],"summary":"HTTP/1 client connection desynchronization after CONNECT rejection in net/http"}