The kvm_apic_has_events function in arch/x86/kvm/lapic.h in the Linux kernel through 4.1.3 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by leveraging /dev/kvm access for an ioctl call.<a href=http://cwe.mitre.org/data/definitions/476.html>CWE-476: NULL Pointer Dereference</a> http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-4692