{"id":"CVE-2026-65600","aliases":["GHSA-cxjq-mrr5-89rv","GO-2026-6208"],"url":"https://o3.security/vulnerability/CVE-2026-65600","summary":"Traefik before v2.11.52 Authentication Bypass via ReplacePathRegex","details":"Traefik versions <= v2.11.51, >= v3.6.0 <= v3.6.22, and >= v3.7.0 <= v3.7.6 contain an authentication bypass via path traversal in the ReplacePathRegex middleware. When ReplacePathRegex is configured with a regex that captures user-controlled path segments without a mandatory path separator (e.g. regex \"^/api(.*)\", replacement \"/$1\"), the middleware forwards the replaced path to the backend without validating that it matches its normalized form. An unauthenticated remote attacker can send a crafted request (e.g. GET /api../admin) that produces an un-normalized path such as /../admin, which a backend that normalizes paths resolves to a protected route, bypassing authentication middleware. Fixed in v2.11.52, v3.6.23, and v3.7.7.","published":"2026-07-22T11:21:46.783Z","modified":"2026-09-09T18:26:44.265736591Z","cvss":null,"epss":{"score":0.00412,"percentile":0.3494,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","fixedVersion":"2.11.52"},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","fixedVersion":"3.6.23"},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","fixedVersion":"3.7.7"},{"ecosystem":"Go","name":"github.com/traefik/traefik","fixedVersion":null}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/65xxx/CVE-2026-65600.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-cxjq-mrr5-89rv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-65600"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/traefik-before-authentication-bypass-via-replacepathregex"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-09T18:26:44.265736591Z"}}