{"id":"CVE-2026-85596","state":"PUBLISHED","title":"Traefik v3.7 Authentication Bypass via TLS Option Conflict","description":"Traefik versions >= v3.7.0 and <= v3.7.10 contain an authentication bypass in the Kubernetes Ingress NGINX provider. The TLS option generated for an Ingress carrying the nginx.ingress.kubernetes.io/auth-tls-secret annotation was named after the Ingress namespace and name. As a result, two Ingress objects sharing the same host, the same client CA secret, and the same client-authentication mode produced two distinct TLS option names for that host. Traefik treats this as a TLS options conflict and falls back to the entry point's default TLS configuration, which does not request a client certificate, so a route configured with nginx.ingress.kubernetes.io/auth-tls-verify-client: \"on\" becomes reachable without a client certificate. 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The TLS option generated for an Ingress carrying the nginx.ingress.kubernetes.io/auth-tls-secret annotation was named after the Ingress namespace and name. As a result, two Ingress objects sharing the same host, the same client CA secret, and the same client-authentication mode produced two distinct TLS option names for that host. Traefik treats this as a TLS options conflict and falls back to the entry point's default TLS configuration, which does not request a client certificate, so a route configured with nginx.ingress.kubernetes.io/auth-tls-verify-client: \"on\" becomes reachable without a client certificate. Only the v3.7 line is affected; the issue is fixed in v3.7.11."}],"affected":[{"vendor":"traefik","product":"traefik","packageURL":"pkg:golang/github.com/traefik/traefik/v3","defaultStatus":"unaffected","versions":[{"version":"3.7.0","status":"affected","lessThanOrEqual":"3.7.10","versionType":"semver"}]}],"references":[{"url":"https://github.com/traefik/traefik/security/advisories/GHSA-j994-9gqj-9hwq","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-j994-9gqj-9hwq)"},{"url":"https://www.vulncheck.com/advisories/traefik-3.7-authentication-bypass-via-tls-option-conflict","name":"VulnCheck Advisory: Traefik v3.7 Authentication Bypass via TLS Option Conflict","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":8.2,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-287","lang":"en","description":"Improper Authentication","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-10-08T15:51:48.871Z"},"datePublic":"2026-08-21T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7.0","versionEndIncluding":"3.7.12"}]}]}],"credits":[{"lang":"en","value":"james-yusuke","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-10T14:19:24.535836Z","id":"CVE-2026-85596","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-10T15:09:29.432Z"}}]}}}