---
id: CVE-2026-47220
title: >-
  Envoy is an open source edge and service proxy designed for cloud-native
  applications
summary: >-
  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_FIRS…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-476
published: '2026-06-26'
updated: '2026-06-29'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-47220'
references:
  - url: >-
      https://github.com/envoyproxy/envoy/security/advisories/GHSA-j9wh-4qfm-wf2v
    label: security-advisories@github.com
  - url: >-
      https://github.com/envoyproxy/envoy/security/advisories/GHSA-j9wh-4qfm-wf2v
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00665
epssPercentile: 0.49606
ingestedAt: '2026-06-29T14:29:18.206Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.