hw/ppc/spapr.c in QEMU through 3.1.0 allows Information Exposure because the hypervisor shares the /proc/device-tree/system-id and /proc/device-tree/model system attributes with a guest.
lists.opensuse.org/opensuse-security-announce/2019-04/msg00094.html
lists.opensuse.org/opensuse-security-announce/2019-05/msg00040.html
www.openwall.com/lists/oss-security/2019/02/21/1
www.securityfocus.com/bid/107115
lists.gnu.org/archive/html/qemu-devel/2019-02/msg04821.html
security.netapp.com/advisory/ntap-20190411-0006/