{"id":"CVE-2022-23632","aliases":["GHSA-hrhx-6h34-j5hc","GO-2022-0325"],"url":"https://o3.security/vulnerability/CVE-2022-23632","summary":"Traefik skips the router TLS configuration when the host header is an FQDN","details":"### Impact\n\nPeople that configure mTLS between Traefik and clients.\n\nFor a request, the TLS configuration choice can be different than the router choice, which implies the use of a wrong TLS configuration.\n\n- When sending a request using FQDN handled by a router configured with a dedicated TLS configuration, the TLS configuration falls back to the default configuration that might not correspond to the configured one.\n\n- If the CNAME flattening is enabled, the selected TLS configuration is the SNI one and the routing uses the CNAME value, so this can skip the expected TLS configuration.\n\n### Patches\n\nTraefik v2.6.x: https://github.com/traefik/traefik/releases/tag/v2.6.1\n\n### Workarounds\n\nAdd the FDQN to the host rule:\n\nExample:\n\n```yml\n  whoami:\n    image: traefik/whoami:v1.7.1\n    labels:\n      traefik.http.routers.whoami.rule: Host(`whoami.example.com`, `whoami.example.com.`)\n      traefik.http.routers.whoami.tls: true\n      traefik.http.routers.whoami.tls.options: mtls@file\n```\n\nThere is no workaround if the CNAME flattening is enabled.\n\n### For more information\n\nIf you have any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/issues).\n","published":"2022-02-17T14:55:10Z","modified":"2026-08-12T03:51:37.752141269Z","cvss":{"score":7.4,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","fixedVersion":"2.6.1"}],"fix":{"url":"https://github.com/traefik/traefik/pull/8764","label":"traefik/traefik#8764"},"references":[{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v2.6.1"},{"type":"WEB","url":"https://www.oracle.com/security-alerts/cpujul2022.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/23xxx/CVE-2022-23632.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-hrhx-6h34-j5hc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-23632"},{"type":"FIX","url":"https://github.com/traefik/traefik/pull/8764"},{"type":"PACKAGE","url":"https://github.com/traefik/traefik"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:37.752141269Z"}}