configurationwatcher.go in Traefik 2.x before 2.1.4 and TraefikEE 2.0.0 mishandles the purging of certificate contents from providers before logging.

Traefik before 2.4.5 allows the loading of IFRAME elements from other domains.

Traefik is an HTTP reverse proxy and load balancer. Prior to version 2.4.13, there exists a potential header vulnerability in Traefik's handling of the Connection header. Active exploitation of this issue is unlikely, as it requires that a removed header would lead to a privilege escalation, however, the Traefik team has addressed this issue to prevent any potential abuse. If one has a chain of Traefik middlewares, and one of them sets a request header, then sending a request with a certain Connection header will cause it to be removed before the request is sent. In this case, the backend does not see the request header. A patch is available in version 2.4.13. There are no known workarounds aside from upgrading.