PatchTheCVECVE-2026-85594: Traefik versions from v3.7.1 fail to enforce crossProviderNamespaces restrictions on the traefik.ingress.kuber
CVE-2026-85594 is a critical-severity flaw (CVSS 9.8) affecting traefik. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
- Critical severity
- Public exploit reference
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 59%) |
| CISA exploited list | No |
| Weakness | CWE-639 |
| Published | 2026-09-04 |
| Last modified | 2026-10-08 |
Last updated 2026-10-08 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-85594?
traefik: upgrade to 3.7.11. Exact commands for each OS are on this page.
Is CVE-2026-85594 being exploited?
CVE-2026-85594 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-85594 affect?
CVE-2026-85594 affects traefik. Severity is critical (CVSS 9.8). 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 a
How urgent is CVE-2026-85594?
Priority 55/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action
Software pages
Kubernetes vulnerabilities · Traefik vulnerabilities
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