libvirt before 2.2 includes Ceph credentials on the qemu command line when using RADOS Block Device (aka RBD), which allows local users to obtain sensitive information via a process listing.
https://wiki.openstack.org/wiki/OSSN/OSSN-0079
https://bugzilla.redhat.com/show_bug.cgi?id=1245647
https://bugs.launchpad.net/ossn/+bug/1686743