CVE-2026-47220

EUVD-2026-39829
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 34.98%
Affected Products (NVD)
VendorProductVersion
envoyproxyenvoy
1.37.0 ≤
𝑥
< 1.37.5
envoyproxyenvoy
1.38.0 ≤
𝑥
< 1.38.3
𝑥
= Vulnerable software versions
Common Weakness Enumeration
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