IOHIDFamily in Apple iOS before 9.3, OS X before 10.11.4, tvOS before 9.2, and watchOS before 2.2 allows attackers to obtain sensitive kernel memory-layout information via a crafted app.
https://support.apple.com/HT205641
https://support.apple.com/HT205640
https://support.apple.com/HT205637
https://support.apple.com/HT205635
http://www.securitytracker.com/id/1035353
http://lists.apple.com/archives/security-announce/2015/Dec/msg00005.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00002.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00001.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00000.html