{"id":"CVE-2026-65601","aliases":["GHSA-qq9q-x9w4-chhj","GO-2026-6198"],"url":"https://o3.security/vulnerability/CVE-2026-65601","summary":"Traefik before 3.7.7 Namespace Confusion via HTTPRoute ExtensionRef","details":"Traefik versions 3.7.0 through 3.7.6 contain a namespace confusion vulnerability in the Kubernetes Gateway API provider. When resolving HTTPRoute.spec.rules[].backendRefs[].filters[].extensionRef, Traefik used the backend Service namespace instead of the HTTPRoute namespace. A low-privileged route author holding a ReferenceGrant for a cross-namespace Service could therefore bind a Traefik Middleware from the backend namespace without a separate grant for that middleware, potentially injecting trusted reverse-proxy identity headers into downstream requests. The issue is fixed in version 3.7.7.","published":"2026-07-22T11:21:47.468Z","modified":"2026-08-18T15:10:54.357323811Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"Traefik","fixedVersion":"3.7.7"}],"fix":{"url":"https://github.com/traefik/traefik/commit/26c96a3935cafb473f4a5bae1886560d9aa4e4f0","label":"traefik/traefik@26c96a3"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/65xxx/CVE-2026-65601.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-qq9q-x9w4-chhj"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-65601"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/traefik-before-namespace-confusion-via-httproute-extensionref"},{"type":"FIX","url":"https://github.com/traefik/traefik/commit/26c96a3935cafb473f4a5bae1886560d9aa4e4f0"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-18T15:10:54.357323811Z"}}