# CVE-2026-73547: Envoy ext_authz: request `:path` pseudoheader dereferenced w/o null check

> CVE-2026-73547: Envoy ext_authz: request `:path` pseudoheader dereferenced w/o null check. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-73547
Last updated: 2026-10-06T15:34:36Z

- Published: 2026-09-21 19:47 UTC · Updated: 2026-10-06 15:34 UTC · Assigner: GitHub\_M
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 0.55%, 46th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-20, CWE-476

## Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy's ext\_authz filter assumes that a request contains a :path pseudoheader when applying query\_parameters\_to\_set or query\_parameters\_to\_remove from an authorization response. A path-less CONNECT request makes request\_headers\_-\>Path() return null, and Filter::onComplete dereferences that pointer while parsing the query string. An unauthenticated downstream client can crash the Envoy process when the filter and authorization response use query-parameter mutation. The relevant scope boundary is that the deployment must accept path-less CONNECT and configure ext\_authz query-parameter mutation. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.

## Affected vendors and products

- envoyproxy: envoy

## Tracked companies

- [Google Cloud](https://rewindex.com/company/google-cloud.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-73547)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-73547)
- [https://github.com/envoyproxy/envoy/commit/064af2e61d0d1c421490d9e3e6e643c5d117ffe4](https://github.com/envoyproxy/envoy/commit/064af2e61d0d1c421490d9e3e6e643c5d117ffe4)
- [https://github.com/envoyproxy/envoy/commit/5f3b8e9b2b8a787a63202d35bb38820f3e9271fe](https://github.com/envoyproxy/envoy/commit/5f3b8e9b2b8a787a63202d35bb38820f3e9271fe)
- [https://github.com/envoyproxy/envoy/commit/838f8ffd9d7b5217682a22ee33470d4c7afb7e98](https://github.com/envoyproxy/envoy/commit/838f8ffd9d7b5217682a22ee33470d4c7afb7e98)
- [https://github.com/envoyproxy/envoy/commit/c3170d7c747e51bb8254378ea89afc03d3e71929](https://github.com/envoyproxy/envoy/commit/c3170d7c747e51bb8254378ea89afc03d3e71929)
- [https://github.com/envoyproxy/envoy/releases/tag/v1.36.10](https://github.com/envoyproxy/envoy/releases/tag/v1.36.10)
- [https://github.com/envoyproxy/envoy/releases/tag/v1.37.6](https://github.com/envoyproxy/envoy/releases/tag/v1.37.6)
- [https://github.com/envoyproxy/envoy/releases/tag/v1.38.4](https://github.com/envoyproxy/envoy/releases/tag/v1.38.4)
- [https://github.com/envoyproxy/envoy/releases/tag/v1.39.1](https://github.com/envoyproxy/envoy/releases/tag/v1.39.1)
- [https://github.com/envoyproxy/envoy/security/advisories/GHSA-87ph-jqwm-pg6r](https://github.com/envoyproxy/envoy/security/advisories/GHSA-87ph-jqwm-pg6r)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-73547 · Markdown: https://rewindex.com/cve/CVE-2026-73547.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-73547 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:15:17.046Z