The Page Loading implementation in WebKit in Apple iOS before 9.3 and Safari before 9.1 mishandles character encoding during access to cached data, which allows remote attackers to bypass the Same Origin Policy and obtain sensitive information via a crafted web site.
https://support.apple.com/HT206171
https://support.apple.com/HT206166
http://www.securitytracker.com/id/1035353
http://www.securityfocus.com/archive/1/537948/100/0/threaded
http://lists.apple.com/archives/security-announce/2016/Mar/msg00005.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00000.html