WebKit in Apple iOS before 10, iTunes before 12.5.1 on Windows, and Safari before 10 allows remote attackers to conduct DNS rebinding attacks against non-HTTP Safari sessions by leveraging HTTP/0.9 support.
http://lists.apple.com/archives/security-announce/2016/Sep/msg00007.html
http://lists.apple.com/archives/security-announce/2016/Sep/msg00008.html
http://lists.apple.com/archives/security-announce/2016/Sep/msg00012.html
https://support.apple.com/HT207143
https://support.apple.com/HT207157