IOHIDFamily in Apple iOS before 8.1.3, Apple OS X before 10.10.2, and Apple TV before 7.0.3 does not properly initialize event queues, which allows attackers to execute arbitrary code in a privileged context or cause a denial of service (NULL pointer dereference) via a crafted app.
http://www.securitytracker.com/id/1031650
http://support.apple.com/HT204246
http://support.apple.com/HT204245
http://support.apple.com/HT204244
http://lists.apple.com/archives/security-announce/2015/Jan/msg00003.html
http://lists.apple.com/archives/security-announce/2015/Jan/msg00001.html
http://lists.apple.com/archives/security-announce/2015/Jan/msg00000.html