CVE-2026-65601: Traefik before 3.7.7 Namespace Confusion via HTTPRoute ExtensionRef
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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 3.7.7Patch Traefik before 3.7.7 Namespace Confusion via HTTPRoute ExtensionRef
Event History
Frequently Asked Questions
What is the severity of CVE-2026-65601?
CVE-2026-65601 has a medium severity rating of 5.3 according to the CVSS scores.
How do I fix CVE-2026-65601?
To fix CVE-2026-65601, upgrade Traefik to version 3.7.7 or later.
What software is affected by CVE-2026-65601?
CVE-2026-65601 affects Traefik versions 3.7.0 through 3.7.6.
What does CVE-2026-65601 entail?
CVE-2026-65601 is a namespace confusion vulnerability in the Kubernetes Gateway API provider that misuses the backend Service namespace during HTTP route resolution.
When was CVE-2026-65601 published?
CVE-2026-65601 was published on July 22, 2026.