hw/sparc64/sun4u.c in QEMU 3.1.50 is vulnerable to a NULL pointer dereference, which allows the attacker to cause a denial of service via a device driver.
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00000.html
https://fakhrizulkifli.github.io/posts/2019/01/03/CVE-2019-5008/