CVE-2026-73513

Envoy: oghttp2 upstream trailers incorrect handling

Published: Sep 21, 2026Updated: Sep 23, 2026 Sources: CVE List NVDCWE-20

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 optional oghttp2 upstream HTTP/2 codec accepts a response trailer HEADERS frame without END_STREAM. Envoy completes and deferred-deletes the ActiveRequest while oghttp2 keeps the stream open, leaving ClientStreamImpl with a dangling response_decoder_ reference. A later frame on the stream can dispatch through the freed object and crash the process. The relevant scope boundary is that the default nghttp2 codec rejects the malformed trailers, and the trigger is upstream-only with oghttp2 enabled. 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-20 CWE-416

Affected Products

envoyproxy

oss-project·USaka envoy proxy, envoy

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/commit/0d33268d7d8cdc5c8ffef462e0cceefa56156b72

github.com

https://github.com/envoyproxy/envoy/commit/3df69eeee220d6a4088cfdd3be79b55e2e6d3514

github.com

https://github.com/envoyproxy/envoy/commit/c4610b6c85d72ed01e014c2a1aba2934a2b774e9

github.com

and 5 more references View all →

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