Traefik is an open source HTTP reverse proxy and load balancer. In affected versions there is a potential vulnerability in Traefik managing TLS connections. A router configured with a not well-formatted TLSOption is exposed with an empty TLSOption. For instance, a route secured using an mTLS connection set with a wrong CA file is exposed without verifying the client certificates. Users are advised to upgrade to version 2.9.6. Users unable to upgrade should check their logs to detect the error messages and fix your TLS options.
https://github.com/traefik/traefik/security/advisories/GHSA-468w-8x39-gj5v
https://github.com/traefik/traefik/releases/tag/v2.9.6
https://github.com/traefik/traefik/commit/7e3fe48b80083b41e9ff82a474a36484cabc701a