An authentication bypass flaw was found in the smart_proxy_dynflow component used by Foreman. A malicious attacker can use this flaw to remotely execute arbitrary commands on machines managed by vulnerable Foreman instances, in a highly privileged context.
https://github.com/theforeman/smart_proxy_dynflow/pull/54
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-14643