Improper certificate validation in Traefik - CVE-2025-66491
Published: December 8, 2025
Vulnerability identifier: #VU119253
CSH Severity: Medium
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-66491
CWE-ID: CWE-295
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform MitM attack.
the vulnerability exists due to an error in the Traefik NGINX provider managing the nginx.ingress.kubernetes.io/proxy-ssl-verify annotation. A remote attacker can perform MitM attack.
Affected software
Traefik
How to mitigate CVE-2025-66491
Install updates from vendor's website.
Traefik - update to 3.6.3