The mach_port_kobject interface in the kernel in Apple iOS before 8.1.3 and Apple TV before 7.0.3 does not properly restrict kernel-address and heap-permutation information, which makes it easier for attackers to bypass the ASLR protection mechanism via a crafted app.
https://support.apple.com/HT204413
http://www.securitytracker.com/id/1031652
http://www.securityfocus.com/bid/72334
http://support.apple.com/HT204246
http://support.apple.com/HT204245
http://lists.apple.com/archives/security-announce/2015/Mar/msg00002.html
http://lists.apple.com/archives/security-announce/2015/Jan/msg00001.html
http://lists.apple.com/archives/security-announce/2015/Jan/msg00000.html