Double free vulnerability in Apple iOS before 8 and Apple TV before 7 allows local users to gain privileges or cause a denial of service (device crash) via vectors related to Mach ports.
http://archives.neohapsis.com/archives/bugtraq/2014-09/0106.html
http://archives.neohapsis.com/archives/bugtraq/2014-09/0107.html
http://archives.neohapsis.com/archives/bugtraq/2014-10/0101.html
https://exchange.xforce.ibmcloud.com/vulnerabilities/96090
https://support.apple.com/kb/HT6535
http://support.apple.com/kb/HT6441