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.

INFO

Published Date :

2025-12-09T00:38:39.208Z

Last Modified :

2025-12-09T16:03:28.511Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2025-66491 vulnerability.

Vendors Products
Traefik
  • Traefik
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-66491.

URL Resource
https://github.com/traefik/traefik/commit/14a1aedf5704673d875d210d7bacf103a43c77e4 cve-icon cve-icon cve-icon
https://github.com/traefik/traefik/releases/tag/v3.6.3 cve-icon cve-icon cve-icon
https://github.com/traefik/traefik/security/advisories/GHSA-7vww-mvcr-x6vj cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2025-66491 cve-icon
https://www.cve.org/CVERecord?id=CVE-2025-66491 cve-icon
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