Openshift/oauth-proxy: openshift/oauth-proxy: unauthenticated identity header injection on whitelisted paths

A flaw was found in openshift/oauth-proxy. On paths configured to bypass authentication (skip-auth-regex), the proxy forwards client-supplied identity headers (X-Forwarded-User, X-Forwarded-Email, X-Forwarded-Access-Token) to the upstream application without stripping them. An unauthenticated attacker can inject forged identity headers on whitelisted paths.