CVE-2026-73511CWE-289CWE-436

CVE-2026-73511

Medium · published September 22, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
30.4
In the wild
Unconfirmed
What it is

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 normally matches the raw request path, while servlet backends such as Apache Tomcat strip semicolon matrix parameters from each path segment before resolving the resource. Envoy's ignore_path_parameters_in_path_matching option instead truncates at the first semicolon and still does not match per-segment backend behavior. A remote client can use a parameterized protected segment, or a parameter on an earlier segment, to make Envoy select an unprotected fallback while the backend resolves the protected resource. The relevant scope boundary is that the bypass requires both a path-based Envoy decision and a backend that strips semicolon parameters per segment. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00376 · 30.4th percentile
Weaknesses
CWE-289 · Authentication Bypass by Alternate Name; CWE-436 · Interpretation Conflict
Published
2026-09-22T01:17Z
Affected products (4)
ProductVersionsFixed in
envoyproxy/envoy< 1.36.101.36.10
envoyproxy/envoy≥ 1.37.0, < 1.37.61.37.6
envoyproxy/envoy≥ 1.38.0, < 1.38.41.38.4
envoyproxy/envoy≥ 1.39.0, < 1.39.11.39.1
References (9)
EPSS history
Timeline
  • 23 SEP 03:48Z
    EPSS moved — → 1%
    epss
  • 21 SEP 20:20Z
    Envoy: Potential path-matching/authentication bypass when using Envoy in combination with a backend stripping per-segment path (matrix) parameters (e.g. Apache Tomcat)
    cvelistv5