Interpretation Conflict in envoy - CVE-2026-73511
Published: August 26, 2026
Vulnerability identifier: #VU145863
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-73511
CWE-ID: CWE-436
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass authentication or authorization checks.
The vulnerability exists due to interpretation conflict in Envoy path matching when processing request paths containing per-segment path parameters with a backend that strips those parameters per segment. A remote attacker can send a specially crafted request path to bypass authentication or authorization checks.
Exploitation requires a deployment in which Envoy makes path-based security decisions and the backend strips matrix parameters from each path segment.
Affected software
envoy
Istio
Istio
How to mitigate CVE-2026-73511
Install security update from vendor's website.
envoy - addressed in versions 1.36.10, 1.37.6, 1.38.4, 1.39.1
Istio - addressed in versions 1.29.7, 1.30.4
Istio - addressed in versions 1.29.7, 1.30.4