Is CVE-2026-73553 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-73553 being exploited in the wild.

How severe is CVE-2026-73553?

High severity, with a CVSS score of 7.5, published 21 September 2026.

Which products and versions are affected?

Envoy before 1.36.10, 1.37.6, 1.38.4, and 1.39.1.

Is there a fix for CVE-2026-73553?

A patch was published on 2026-08-26: Patches released in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-73553 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-73553?

Check whether you run Envoy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-73553: Envoy authorization bypass via path parameter inconsistency

CVE-2026-73553 · Severity: high · CVSS 7.5 · Published 2026-09-21

Envoy is a network proxy used to route and control traffic in cloud applications. When a configuration option for ignoring path parameters is enabled, Envoy's router and authorization filter handle URLs inconsistently—allowing an attacker to append path parameters (like /admin;x) to bypass authorization policies while still reaching the protected endpoint. This enables unauthenticated users to access resources that should be blocked.

Technologies: Envoy. Vendors: Envoy.

Quick answers

Is CVE-2026-73553 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-73553 being exploited in the wild.
How severe is CVE-2026-73553?: High severity, with a CVSS score of 7.5, published 21 September 2026.
Which products and versions are affected?: Envoy before 1.36.10, 1.37.6, 1.38.4, and 1.39.1.
Is there a fix for CVE-2026-73553?: A patch was published on 2026-08-26: Patches released in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-73553 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-73553?: Check whether you run Envoy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

When ignore_path_parameters_in_path_matching is enabled, the router strips path parameters (text after semicolons) during route matching, but the RBAC filter's PathMatcher and UriTemplateMatcher do not, creating an authorization bypass. An unauthenticated attacker can append path parameters to requests to evade DENY rules while the router still forwards the request to the protected backend. The vulnerability requires both the route configuration option and a path-based RBAC rule to be present, with the route matching after parameter stripping.

Affected products

Envoy Envoy before 1.36.10, 1.37.6, 1.38.4, and 1.39.1

Timeline

2026-09-21: disclosed
2026-08-26: patched: Patches released in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1

References

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