CVE-2026-47220

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.

CVSS 3.1

7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

0.7% chance of exploitation in the next 30 days; higher than 51% of CVEs (scores of 2026-10-25)

CWE

CWE-476

Published

2026-06-26

Modified

2026-10-25

Record from

the NVD, synced 2026-10-25

Affected

• envoyproxy:envoy

References

• https://github.com/envoyproxy/envoy/security/advisories/GHSA-j9wh-4qfm-wf2v
• https://access.redhat.com/security/cve/CVE-2026-47220
• https://bugzilla.redhat.com/show_bug.cgi?id=2493652
• https://github.com/envoyproxy/envoy/security/advisories/GHSA-j9wh-4qfm-wf2v
• https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47220.json

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