{"id":"CVE-2026-85594","summary":"Traefik v3.7.1 crossProviderNamespaces Bypass via Service Middleware","details":"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.","aliases":["GHSA-m6wx-622r-48r9"],"modified":"2026-10-28T02:30:28.585597301Z","published":"2026-09-04T11:29:58.771Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-639"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85594.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85594.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-m6wx-622r-48r9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-85594"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/traefik-3.7.1-crossprovidernamespaces-bypass-via-service-middleware"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/traefik/traefik","events":[{"introduced":"fa49e2bcad7ffd8a80accdf1fae1ae480913d93d"},{"fixed":"faa1eb590646aed94e561e24a59be0c47353ae95"}],"database_specific":{"extracted_events":[{"range":[{"introduced":"3.7.1"},{"last_affected":"3.7.12"}],"source":"AFFECTED_FIELD","strategy":"StandardRange"},{"source":"CPE_RANGE","cpe":"cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*","range":[{"introduced":"0"},{"fixed":"3.7.11"}]}]}}],"versions":["v3.7.10","v3.7.9","v3.7.8","v3.7.7","v3.7.6","v3.7.5","v3.7.4","v3.7.3","v3.7.2","v3.7.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-85594.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V4","score":"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"}]}