{"id":"CVE-2026-26311","aliases":["BIT-envoy-2026-26311","GHSA-84xm-r438-86px"],"url":"https://o3.security/vulnerability/CVE-2026-26311","summary":"Envoy HTTP: filter chain execution on reset streams causing UAF crash","details":"Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, a logic vulnerability in Envoy's HTTP connection manager (FilterManager) that allows for Zombie Stream Filter Execution. This issue creates a \"Use-After-Free\" (UAF) or state-corruption window where filter callbacks are invoked on an HTTP stream that has already been logically reset and cleaned up. The vulnerability resides in source/common/http/filter_manager.cc within the FilterManager::decodeData method. The ActiveStream object remains valid in memory during the deferred deletion window. If a DATA frame arrives on this stream immediately after the reset (e.g., in the same packet processing cycle), the HTTP/2 codec invokes ActiveStream::decodeData, which cascades to FilterManager::decodeData. FilterManager::decodeData fails to check the saw_downstream_reset_ flag. It iterates over the decoder_filters_ list and invokes decodeData() on filters that have already received onDestroy(). This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.","published":"2026-03-10T19:14:41.645Z","modified":"2026-08-12T03:51:36.990268057Z","cvss":{"score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/envoyproxy/envoy","fixedVersion":null},{"ecosystem":"Go","name":"github.com/envoyproxy/envoy","fixedVersion":null},{"ecosystem":"Go","name":"github.com/envoyproxy/envoy","fixedVersion":null},{"ecosystem":"Go","name":"github.com/envoyproxy/envoy","fixedVersion":null}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26311.json"},{"type":"ADVISORY","url":"https://github.com/envoyproxy/envoy/security/advisories/GHSA-84xm-r438-86px"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-26311"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:36.990268057Z"}}