CVE-2026-73553

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, When ignore_path_parameters_in_path_matching is enabled, Envoy's router strips the semicolon suffix before matching but the RBAC url_path matcher evaluates the raw path. A downstream request such as /admin;x can therefore miss a DENY rule for /admin while the router still selects the protected /admin backend. The inconsistent canonicalization allows an unauthenticated client to bypass path-based authorization. The relevant scope boundary is that the route option and a path-based RBAC rule must both be present, and the protected route must match after stripping. 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-77x5-xqjg-hprq

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/e6d5fe885409ebb335ed3934a167f0bcfea471f2

https://github.com/envoyproxy/envoy/commit/b6ec9b66cc33a415e2fa81a6fa8363cac4772dd1

https://github.com/envoyproxy/envoy/commit/6a703a375a20e3bf98140ee5f5522c614adee7b6

https://github.com/envoyproxy/envoy/commit/0be4a0302ea94a894e470817c2edfbd5ed90d273

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-84120

Details

Source: Mitre, NVD

Published: 2026-09-21

Updated: 2026-10-05

Risk Information

CVSS v2

Base Score: 6.1

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

Severity: Medium

CVSS v3

Base Score: 7.5

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

Severity: High

EPSS

EPSS: 0.00507