CVE-2026-41174

Описание

Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is a potential vulnerability in Traefik's Kubernetes CRD provider cross-namespace isolation enforcement. When providers.kubernetesCRD.allowCrossNamespace=false, Traefik correctly rejects direct cross-namespace middleware references from IngressRoute objects, but fails to apply the same restriction to middleware references nested inside a Chain middleware's spec.chain.middlewares[]. An actor with permission to create or update Traefik CRDs in their own namespace can exploit this to cause Traefik to resolve and apply middleware objects from another namespace, bypassing the documented isolation boundary. This issue has been patched in versions 2.11.43, 3.6.14, and 3.7.0-rc.2.

A flaw was found in Traefik, an HTTP reverse proxy and load balancer. When the Kubernetes Custom Resource Definition (CRD) provider's allowCrossNamespace setting is false, Traefik incorrectly processes nested middleware references. An attacker with permissions to create or update Traefik CRDs in their own namespace can exploit this to bypass the intended cross-namespace isolation, allowing Traefik to apply middleware objects from other namespaces. This could lead to unauthorized access or manipulation of resources across namespaces.