An issue was discovered in certain Apple products. iOS before 11 is affected. Safari before 11 is affected. iCloud before 7.0 on Windows is affected. The issue involves the "WebKit" component. It allows remote attackers to spoof the address bar.
https://support.apple.com/HT208142
https://support.apple.com/HT208116
https://support.apple.com/HT208112
http://www.securitytracker.com/id/1039385