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.
https://github.com/traefik/traefik/security/advisories/GHSA-7vww-mvcr-x6vj
https://github.com/traefik/traefik/releases/tag/v3.6.3
https://github.com/traefik/traefik/commit/14a1aedf5704673d875d210d7bacf103a43c77e4