CVEvulnerability

CVE-2026-41174

4.8 MEDIUM Published 2026-04-30 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-04-30
Last modified
2026-06-17
Assigner
[email protected]
CVSS 4.0 ([email protected])
4.8 MEDIUM — CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1 ([email protected])
6.4 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Weaknesses
CWE-653, CWE-863

Description

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.

Affected configurations

• traefik traefik (< 2.11.43) • traefik traefik (>= 3.0.0 < 3.6.14) • traefik traefik 3.7.0

Related

Weakness · CWE (2)

  • CWE-653 Improper Isolation or Compartmentalization weakness
  • CWE-863 Incorrect Authorization weakness

References