Description
Traefik versions from v3.7.1 fail to enforce crossProviderNamespaces restrictions on the traefik.ingress.kubernetes.io/service.middlewares Service annotation in the Kubernetes Ingress provider. A namespace-limited tenant excluded from the allowlist can attach an operator-owned middleware to its Service, and if that middleware injects backend credentials, recover them at a controlled backend.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| traefik | traefik | 3.7.1 – ≤ 3.7.12 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | traefik-3.6 | No fix yet | — |
References
- GitHub Security Advisory (GHSA-m6wx-622r-48r9) vendor-advisory
- VulnCheck Advisory: Traefik v3.7.1 crossProviderNamespaces Bypass via Service Middleware third-party-advisory