CVE-2026-73512

Envoy: use-after-free in QUIC on internal redirects

Published: Sep 21, 2026Updated: Sep 23, 2026 Sources: CVE List NVDCWE-416

7.5HIGH

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-416

Affected Products

envoyproxy

oss-project·USaka envoy, envoy proxy

envoyOn-prem

Cloud & SaaS / api-gateway

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

Privilege Escalation

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References

https://github.com/envoyproxy/envoy/security/advisories/GHSA-r6j2-mrm5-72mg

github.com

https://github.com/envoyproxy/envoy/commit/29dbaae4a9971011e2f1948acfaf383296e901ea

github.com

https://github.com/envoyproxy/envoy/commit/85495163fdc67364a5258bfe478c34a44f6428b4

github.com

and 6 more references View all →

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