Apple's iCloud system was presented as a safe one in which users can upload their files and keep them safe knowing that Apple protects them against any kind of attacks. The files are encrypted so that no one can access them without the user's consent, but Apple can decrypt and access them at any time. It was normal like Apple have the file decryption key considering that it keeps them on its own servers and the rationale behind holding this key lies in the right of the company to verify the files and to give them to the authorities if this is required.
I can tell you that the iCloud terms and conditions are pretty telling about what the capabilities are at Apple with respect to iCloud, and suggests they can view any and all content. If iCloud data was fully encrypted, they wouldn't be able to review content, provide content to law enforcement, or attempt to identify DMCA violations. If you can access something with a webpage, that means the webserver has the key. Thus we know that Apple could access at least anything iCloud related that shows in the browser.
Apple reserves the right to do whatever it wants with the files published by us in iCloud and I assume that many of you already knew this considering that it was as obvious as possible. Through the terms and conditions of iCloud, Apple has provided full rights over all the files uploaded to its system and anything can be checked, modified or deleted if it is not in accordance with the provisions of the law or with the regulations of the Apple company. Even if those from Cupertino can check any files, you don't have to worry about data security unless you break the law in some way.
