There is a bug in iOS 7 that prevents email attachments from being encrypted on your device. The good news is, Apple's already working on a solution.
An Apple spokesperson told iMore that Apple "is aware of the issue and are working on a fix which will be delivered in a future software update."
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The flaw was first reported by Andreas Kurtz, who noticed that he was able to access email attachments when accessing the iOS 7 file system without entering in a passcode
This isn't supposed to happen because mail attachments are supposed to be protected by Apple's Data Protection technologies. Data Protection is supposed offer users "an additional layer of protection for your email messages attachments, and third-party applications." Read more...
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