{"id":"CVE-2026-71325","aliases":["GHSA-62fc-8686-hfmq","GO-2026-6203"],"url":"https://o3.security/vulnerability/CVE-2026-71325","summary":"Traefik: `allowCrossNamespace=false` bypass via `@kubernetescrd` TraefikService backendRef","details":"Traefik is an open-source edge router that makes publishing services a fun and easy experience. Prior to 2.11.54, 3.6.25, and 3.7.10, cross-namespace @kubernetescrd references are not rejected for TraefikService backend references resolved by the service resolver. A tenant confined by RBAC to a single namespace can therefore bind its own router to a TraefikService owned by another namespace and expose or reroute that namespace's backend, defeating the namespace isolation allowCrossNamespace=false is meant to enforce. This issue is fixed in version 2.11.54, 3.6.25, 3.7.10.","published":"2026-08-06T16:24:56.606Z","modified":"2026-09-18T03:48:29.427683187Z","cvss":null,"epss":{"score":0.00132,"percentile":0.03123,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","fixedVersion":"2.11.54"},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","fixedVersion":"3.6.25"},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","fixedVersion":"3.7.10"},{"ecosystem":"Go","name":"github.com/traefik/traefik","fixedVersion":null}],"fix":{"url":"https://github.com/traefik/traefik/commit/65ebf4b47fbdc33e3856803a5844a404e094d52d","label":"traefik/traefik@65ebf4b"},"references":[{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v2.11.54"},{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v3.6.25"},{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v3.7.10"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71325.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-62fc-8686-hfmq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-71325"},{"type":"FIX","url":"https://github.com/traefik/traefik/commit/65ebf4b47fbdc33e3856803a5844a404e094d52d"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-18T03:48:29.427683187Z"}}