CVE-2026-47220

Envoy: Segmentation fault when using %REQUESTED_SERVER_NAME% in log format

Published: Jun 26, 2026Updated: Jul 15, 2026 Sources: CVE List NVDCWE-476

7.5HIGH

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.37.0 until 1.37.5 and 1.38.3, when the %REQUESTED_SERVER_NAME(X:Y)% is used in log format and host related options is specified, like HOST_FIRST, SNI_FIRST, it's possible to crash Envoy when the specified host header is missing in the request headers. This vulnerability is fixed in 1.37.5 and 1.38.3.

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-476

Affected Products

envoyproxy

oss-project·USaka envoy, envoy proxy

envoyOn-prem

Cloud & SaaS / api-gateway

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Impact

Initial Access

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References

https://github.com/envoyproxy/envoy/security/advisories/GHSA-j9wh-4qfm-wf2v

github.com

https://access.redhat.com/security/cve/CVE-2026-47220

access.redhat.com

https://bugzilla.redhat.com/show_bug.cgi?id=2493652

bugzilla.redhat.com

and 1 more references View all →

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