The "Clear History and Website Data" feature in Apple Safari before 9.1.1, as used in iOS before 9.3.2 and other products, mishandles the deletion of browsing history, which might allow local users to obtain sensitive information by leveraging read access to a Safari directory.
https://support.apple.com/HT206568
https://support.apple.com/HT206565
http://www.securitytracker.com/id/1035888
http://lists.apple.com/archives/security-announce/2016/May/msg00005.html
http://lists.apple.com/archives/security-announce/2016/May/msg00002.html