Foreman versions before 2.3.4 and before 2.4.0 is affected by an improper authorization handling flaw. An authenticated attacker can impersonate the foreman-proxy if product enable the Puppet Certificate authority (CA) to sign certificate requests that have subject alternative names (SANs). Foreman do not enable SANs by default and allow-authorization-extensions
is set to false
unless user change /etc/puppetlabs/puppetserver/conf.d/ca.conf
configuration explicitly.