A bug has been discovered in iOS 7 that causes email attachments to not be encrypted. Before anyone panics, however, in order for an attacker to exploit the bug they'd need to a) steal your device and, b) brute force or jailbreak-bypass the passcode or password, which d) currently means iPhone 4s and later devices running iOS 7.1 or later software aren't at risk. The bug was first reported by Andreas Kurtz:
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