CVE-2026-65601

Traefik versions 3.7.0 through 3.7.6 contain a namespace confusion vulnerability in the Kubernetes Gateway API provider. When resolving HTTPRoute.spec.rules[].backendRefs[].filters[].extensionRef, Traefik used the backend Service namespace instead of the HTTPRoute namespace. A low-privileged route author holding a ReferenceGrant for a cross-namespace Service could therefore bind a Traefik Middleware from the backend namespace without a separate grant for that middleware, potentially injecting trusted reverse-proxy identity headers into downstream requests. The issue is fixed in version 3.7.7.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/commit/26c96a3935cafb473f4a5bae1886560d9aa4e4f0	Patch
https://github.com/traefik/traefik/security/advisories/GHSA-qq9q-x9w4-chhj	Vendor Advisory
https://www.vulncheck.com/advisories/traefik-before-namespace-confusion-via-httproute-extensionref	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-22 12:18

Updated : 2026-08-06 15:36

NVD link : CVE-2026-65601

Mitre link : CVE-2026-65601

CVE.ORG link : CVE-2026-65601

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-863

Incorrect Authorization

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