{"cve":"CVE-2026-41174","nvd":{"published":"2026-04-30T21:16:33.240","modified":"2026-06-17T10:46:16.493","status":"Analyzed","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.","cvss_v4":{"vector":"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","score":4.8},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N","score":6.4},"cwes":["CWE-653","CWE-863"],"references":["https://github.com/traefik/traefik/commit/df00d82fc7f12e07199551832b54de6d0e55414d","https://github.com/traefik/traefik/releases/tag/v2.11.43","https://github.com/traefik/traefik/releases/tag/v3.6.14","https://github.com/traefik/traefik/releases/tag/v3.7.0-rc.2","https://github.com/traefik/traefik/security/advisories/GHSA-xhjw-95fp-8vgq"],"products":["traefik:traefik"],"source":"nvd","synced_at":"2026-10-19T22:33:09.003606135+00:00"},"epss":{"cve":"CVE-2026-41174","score":0.00254,"percentile":0.16958,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-xhjw-95fp-8vgq","url":"https://osv.dev/vulnerability/GHSA-xhjw-95fp-8vgq","summary":"Traefik Kubernetes CRD allows unauthorized cross-namespace middleware binding","modified":"2026-06-25T23:11:34.624569509Z","packages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":[">=3.7.0-ea.1 <3.7.0-rc.2"],"fixed":["3.7.0-rc.2"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":[">=3.0.0-beta1 <3.6.14"],"fixed":["3.6.14"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","ranges":["<2.11.43"],"fixed":["2.11.43"]},{"ecosystem":"Go","name":"github.com/traefik/traefik","purl":"pkg:golang/github.com/traefik/traefik","ranges":["<=1.7.34"],"fixed":[]}]},{"id":"GO-2026-5760","url":"https://osv.dev/vulnerability/GO-2026-5760","summary":"Traefik Kubernetes CRD allows unauthorized cross-namespace middleware binding in github.com/traefik/traefik","modified":"2026-06-25T23:01:44.060043824Z","packages":[{"ecosystem":"Go","name":"github.com/traefik/traefik","purl":"pkg:golang/github.com/traefik/traefik","ranges":["all versions"],"fixed":[]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","ranges":["<2.11.43"],"fixed":["2.11.43"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":[">=3.0.0-beta1 <3.6.14",">=3.7.0-ea.1 <3.7.0-rc.2"],"fixed":["3.6.14","3.7.0-rc.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}