Apple Security Advisory 2013-03-19-2 - Apple TV 5.2.1 is now available and addresses multiple security issues such as execution of unsigned code and information disclosure issues.
bac45d77e98f0ec3e7850f59f1a70b6fb9040d3075c3956d8f3436076e7149bb
Apple Security Advisory 2013-03-19-1 - iOS 6.1.3 is now available and addresses multiple security issues such as execution of unsigned code, permission changes, and more.
824988d29933703818be3b608fa9c3b290c14c3e517b7be5711d61cbb336a117