High 7.0Published Sep 4, 2026

CVE-2026-85594Traefik v3.7.1 crossProviderNamespaces Bypass via Service Middleware

Updated under an hour ago (2026-10-19 09:30 UTC)

Does this affect you?

It affects traefik. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for traefik

Exploited in the last 30 days

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.

CVSS: 7.0 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
Weakness (CWE): CWE-639
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Analyzed
Record last updated: Oct 8, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

traefik traefik traefik:traefik (from the name)	from 3.7.1 through 3.7.12	CNA record
traefik traefik traefik:traefik	before 3.7.11	NVD

References

https://github.com/traefik/traefik/security/advisories/GHSA-m6wx-622r-48r9vendor-advisory
https://www.vulncheck.com/advisories/traefik-3.7.1-crossprovidernamespaces-bypass-via-service-middlewarethird-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.