CVE-2026-47220: Envoyproxy Envoy

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

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.

Affected products

• Envoyproxy Envoy: from 1.37.0, before 1.37.5 (fixed in 1.37.5); from 1.38.0, before 1.38.3 (fixed in 1.38.3)

Published 2026-06-26. Last modified 2026-07-15.