The virDomainGetXMLDesc API in Libvirt before 1.2.11 allows remote read-only users to obtain the VNC password by using the VIRDOMAINXMLMIGRATABLE flag, which triggers the use of the VIRDOMAINXMLSECURE flag.
{ "availability": "No subscription required", "ubuntu_priority": "medium", "binaries": [ { "binary_version": "1.2.2-0ubuntu13.1.7", "binary_name": "libvirt-bin" }, { "binary_version": "1.2.2-0ubuntu13.1.7", "binary_name": "libvirt-dev" }, { "binary_version": "1.2.2-0ubuntu13.1.7", "binary_name": "libvirt-doc" }, { "binary_version": "1.2.2-0ubuntu13.1.7", "binary_name": "libvirt0" }, { "binary_version": "1.2.2-0ubuntu13.1.7", "binary_name": "libvirt0-dbg" } ] }