CVE-2026-47220

HIGH7.5

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

Published Jun 26, 2026

Modified 2 weeks ago

Details

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.

References

WEB

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

WEB

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

DETECTION

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

WEB

https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47220.json

ADVISORY

https://www.cve.org/CVERecord?id=CVE-2026-47220

CVSS Analysis