QEMU (aka Quick Emulator) built with an IDE AHCI emulation support is vulnerable to a null pointer dereference flaw. It occurs while unmapping the Frame Information Structure (FIS) and Command List Block (CLB) entries. A privileged user inside guest could use this flaw to crash the QEMU process instance resulting in DoS.
https://security.gentoo.org/glsa/201604-01
https://lists.gnu.org/archive/html/qemu-devel/2016-01/msg05742.html
https://bugzilla.redhat.com/show_bug.cgi?id=1302057
http://www.securityfocus.com/bid/82235