# CVE-2026-73512: Envoy: use-after-free in QUIC on internal redirects

> CVE-2026-73512: Envoy: use-after-free in QUIC on internal redirects. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-73512
Last updated: 2026-10-05T14:12:31Z

- Published: 2026-09-21 19:51 UTC · Updated: 2026-10-05 14:12 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: 0.87%, 59th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-416

## 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 HttpDatagramHandler caches the current RequestDecoder when Capsule Protocol is enabled. Stream recreation, including an internal redirect, replaces the ActiveStream and updates EnvoyQuicServerStream but does not update the handler's cached pointer. A subsequent HTTP/3 datagram can call decodeData through the freed decoder, causing invalid virtual dispatch and a process crash. The relevant scope boundary is that hTTP/3 datagrams and Capsule Protocol must be enabled, and the request must enter a stream-recreation path such as an internal redirect. 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-2026-73512)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-73512)
- [https://github.com/envoyproxy/envoy/commit/29dbaae4a9971011e2f1948acfaf383296e901ea](https://github.com/envoyproxy/envoy/commit/29dbaae4a9971011e2f1948acfaf383296e901ea)
- [https://github.com/envoyproxy/envoy/commit/85495163fdc67364a5258bfe478c34a44f6428b4](https://github.com/envoyproxy/envoy/commit/85495163fdc67364a5258bfe478c34a44f6428b4)
- [https://github.com/envoyproxy/envoy/commit/c0e46dabc3ac286bbe608e9274776555911aadb9](https://github.com/envoyproxy/envoy/commit/c0e46dabc3ac286bbe608e9274776555911aadb9)
- [https://github.com/envoyproxy/envoy/commit/f2417eec2ff49abe243d484ded916fbc2faca38d](https://github.com/envoyproxy/envoy/commit/f2417eec2ff49abe243d484ded916fbc2faca38d)
- [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-r6j2-mrm5-72mg](https://github.com/envoyproxy/envoy/security/advisories/GHSA-r6j2-mrm5-72mg)

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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-2026-73512 · Markdown: https://rewindex.com/cve/CVE-2026-73512.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-73512 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:15:58.623Z