The ironic-api service in OpenStack Ironic before 4.2.5 (Liberty) and 5.x before 5.1.2 (Mitaka) allows remote attackers to obtain sensitive information about a registered node by leveraging knowledge of the MAC address of a network card belonging to that node and sending a crafted POST request to the v1/drivers/$DRIVER_NAME/vendor_passthru resource.
https://review.openstack.org/332197
https://review.openstack.org/332196
https://review.openstack.org/332195
https://bugs.launchpad.net/ironic/+bug/1572796
https://access.redhat.com/errata/RHSA-2016:1378