CVE-2026-26311
Envoy HTTP: filter chain execution on reset streams causing UAF crash
At a glance
- Source
- NVD
- EPSS
- EPSS 0.36 % · percentile 29 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
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.
Weaknesses (CWE)
- CWE-416 — Use After Free
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · security-advisories@github.com (Secondary) |
Advisories
- GHSA-84xm-r438-86px — Envoy: HTTP - filter chain execution on reset streams causing UAF crash
European references
- ENISA EUVD · EUVD-2026-10804
- GCVE · GCVE-0-2026-26311
Affected configurations (NVD CPE)
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*< 1.34.13cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*≥ 1.35.0 < 1.35.8cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*≥ 1.36.0 < 1.36.5cpe:2.3:a:envoyproxy:envoy:1.37.0:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| envoyproxy · envoy | affected >= 1.37.0, < 1.37.1 ; affected >= 1.36.0, < 1.36.5 ; affected >= 1.35.0, < 1.35.9 ; affected < 1.34.13 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |