Features of the Polymorphic Medley Cipher include:
The task to break the Polymorphic Medley Cipher is several orders of magnitude more difficult than breaking AES alone. This is why we are very confident that this 128 bit cipher protects valuable data reliably in this public challenge. The challenge clearly has primarily an academic value rather than anything else. If the PDF file was encrypted with the standard AES Rijndael cipher, the first participants in this challenge would claim the price after no more than a single day. Why? Well, here's the maths: 6 characters, each character selected from a set of 81 characters: 81^6 = 282,429,536,481 (approx. 282 billion possible key combinations) A brute force attack on AES 128 runs at approx. 4.6 million key combinations per second. In order to try all possible 282 billion key combinations it consequently takes 17 hours AT MAXIMUM. Taking into account that more than four ounces of gold are quite expensive these days - why the heck are we nuts and give away a lot of money that easily? The truth is that the challenge is pretty hard. Of course we are not so stupid to use AES with short keys. Who can take part and what is needed to take part at the challenge? - everybody can ! - it's free ! - you can even find the source code here