5.3
MEDIUM CVSS 3.1
CVE-2026-73511
Envoy: Potential path-matching/authentication bypass when using Envoy in combination with a backend stripping per-segment path (matrix) parameters (e.g. Apache Tomcat)
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 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.

INFO

Published Date :

Sept. 21, 2026, 9:17 p.m.

Last Modified :

Sept. 21, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-73511 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Envoyproxy envoy
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update Envoy to versions 1.36.10, 1.37.6, 1.38.4, or 1.39.1 to fix path parameter matching.
  • Update Envoy to version 1.36.10 or later.
  • Update Envoy to version 1.37.6 or later.
  • Update Envoy to version 1.38.4 or later.
  • Update Envoy to version 1.39.1 or later.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-73511 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-73511 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-73511 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-73511 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 21, 2026

    Action Type Old Value New Value
    Added 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 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
    Added CWE CWE-436
    Added CWE CWE-289
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/73xxx/CVE-2026-73511.json">CVE-2026-73511</a>
    Added Reference https://github.com/envoyproxy/envoy/commit/26d5
    Added Reference https://github.com/envoyproxy/envoy/commit/50f7bfa48dccfee339822e9846b2b8053e07d325
    Added Reference https://github.com/envoyproxy/envoy/commit/b205d1f4982e14ce5693ba94ef84d37e7155e050
    Added Reference https://github.com/envoyproxy/envoy/commit/fcb663752c7055257f5dcc8b6ce6c7c905ebb1ff
    Added Reference https://github.com/envoyproxy/envoy/releases/tag/v1.36.10
    Added Reference https://github.com/envoyproxy/envoy/releases/tag/v1.37.6
    Added Reference https://github.com/envoyproxy/envoy/releases/tag/v1.38.4
    Added Reference https://github.com/envoyproxy/envoy/releases/tag/v1.39.1
    Added Reference https://github.com/envoyproxy/envoy/security/advisories/GHSA-m745-gh6x-349x
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.