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How secure is encrypted zip if some of the files have known plaintext?

How secure is encrypted zip if some of the files have known plaintext?

If I create an encrypted zip file with Winzip (say with 256 bit AES encryption), and some of the files contained in it have publicly known contents (e.g. open source 3rd party libraries), does this compromise the security of the encrypted zip at all?

Asked by: Guest | Views: 69
Total answers/comments: 1
Guest [Entry]

"The original ZIP specification defines an encryption method that is incredibly easy to break, but many vendors have added their own encryption methods onto ZIP, like WinZip's AES that you mention, which is more widely implemented than any other ZIP encryption method.

In general, AES is very secure, but any algorithm can be compromised by a bad implementation. I have not heard of any problems with the WinZip implementation, and it has been compatibly reimplemented in some open-source tools (7-zip, for example), so I think there are probably enough eyes to assume that it's reasonably secure."