{"id":"CVE-2025-66491","revision":"2ab561fe7c304612b2c941ea5f52ee93","records":[{"revision":"2ab561fe7c304612b2c941ea5f52ee93","observedAt":"2026-10-25T03:17:36.152+00:00","statement":{"source":"nvd","id":"CVE-2025-66491","aliases":[],"title":"Traefik is an HTTP reverse proxy and load balancer. Versions 3.5.0 through 3.6.2 have inverted TLS verification logic in the nginx.ingress.kubernetes.io/proxy-ssl-verify annotation. Setting the annotation to \"on\" (intending to enable backen…","description":"Traefik is an HTTP reverse proxy and load balancer. Versions 3.5.0 through 3.6.2 have inverted TLS verification logic in the nginx.ingress.kubernetes.io/proxy-ssl-verify annotation. Setting the annotation to \"on\" (intending to enable backend TLS certificate verification) actually disables verification, allowing man-in-the-middle attacks against HTTPS backends when operators believe they are protected. This issue is fixed in version 3.6.3.","state":0,"publishedAt":"2025-12-09T01:16:55.72+00:00","modifiedAt":"2026-10-14T22:10:00.21+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","score":5.9,"severity":"MEDIUM"}],"references":["https://github.com/traefik/traefik/commit/14a1aedf5704673d875d210d7bacf103a43c77e4","https://github.com/traefik/traefik/releases/tag/v3.6.3","https://github.com/traefik/traefik/security/advisories/GHSA-7vww-mvcr-x6vj"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-66491","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Analyzed","weaknesses":["CWE-295"],"productCriteria":["cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*"],"sourceDates":{"published":"2025-12-09T01:16:55.720","lastModified":"2026-10-14T22:10:00.210"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2025-66491","identifiers":["CVE-2025-66491"]},"retained":false,"historicalAffected":[]}],"coverage":[]}