The v9fs_iov_vunmarshal function in fsdev/9p-iov-marshal.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (NULL pointer dereference and QEMU process crash) by sending an empty string parameter to a 9P operation. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-8578