CVE-2026-47220 HIGH

CVE-2026-47220: Envoy: Segmentation fault when using %REQUESTED_SERVER_NAME% in log format

Vendor Envoyproxy
Product envoy
Weakness CWE-476
Published June 26, 2026
Last update June 30, 2026
View on NVD All CVEs

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

June 26, 2026 CVE published
June 30, 2026 Record updated