As you say knowing that the first two bytes of a valid decrypt must be say the gzip header bytes 0x1f 0x8b does provide a small chink that can potentially be exploited. If you are that paranoid they are easy to hide. Making two passes with the encryption algorithm is one easy way.

cheers

tachyon

In reply to Re^6: Compressing and Encrypting files on Windows by tachyon
in thread Compressing and Encrypting files on Windows by hawtin

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