CVE-2026-73547

high

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, Envoy's ext_authz filter assumes that a request contains a :path pseudoheader when applying query_parameters_to_set or query_parameters_to_remove from an authorization response. A path-less CONNECT request makes request_headers_->Path() return null, and Filter::onComplete dereferences that pointer while parsing the query string. An unauthenticated downstream client can crash the Envoy process when the filter and authorization response use query-parameter mutation. The relevant scope boundary is that the deployment must accept path-less CONNECT and configure ext_authz query-parameter mutation. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.

References

https://docs.cloud.google.com/support/bulletins/index#gcp-2026-057

https://github.com/envoyproxy/envoy/security/advisories/GHSA-87ph-jqwm-pg6r

https://github.com/envoyproxy/envoy/releases/tag/v1.39.1

https://github.com/envoyproxy/envoy/releases/tag/v1.38.4

https://github.com/envoyproxy/envoy/releases/tag/v1.37.6

https://github.com/envoyproxy/envoy/releases/tag/v1.36.10

https://github.com/envoyproxy/envoy/commit/c3170d7c747e51bb8254378ea89afc03d3e71929

https://github.com/envoyproxy/envoy/commit/838f8ffd9d7b5217682a22ee33470d4c7afb7e98

https://github.com/envoyproxy/envoy/commit/5f3b8e9b2b8a787a63202d35bb38820f3e9271fe

https://github.com/envoyproxy/envoy/commit/064af2e61d0d1c421490d9e3e6e643c5d117ffe4

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-84110

Details

Source: Mitre, NVD

Published: 2026-09-21

Updated: 2026-10-06

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

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

Severity: High

EPSS

EPSS: 0.00827