WebKit in Apple iOS before 9.3.3 and Safari before 9.1.2 mishandles about: URLs, which allows remote attackers to bypass the Same Origin Policy via a crafted web site.
lists.apple.com/archives/security-announce/2016/Jul/msg00001.html
lists.apple.com/archives/security-announce/2016/Jul/msg00004.html
packetstormsecurity.com/files/138502/WebKitGTK-SOP-Bypass-Information-Disclosure.html
www.securityfocus.com/archive/1/539295/100/0/threaded
www.securityfocus.com/bid/91835
www.securitytracker.com/id/1036343
support.apple.com/HT206900
support.apple.com/HT206902