app/controllers/api/v1/hosts_controller.rb in Foreman before 1.2.2 does not properly restrict access to hosts, which allows remote attackers to access arbitrary hosts via an API request.
https://bugzilla.redhat.com/show_bug.cgi?id=990374
http://theforeman.org/manuals/1.2/index.html#Releasenotesfor1.2.2