Crypto Challenge contest

[Usr6]

Challenge your knowledge:

With the launch of MysteryTwister C3 you can test your own knowledge by solving a variety of cryptographic challenges.

The MysteryTwister I was started as an international cryptology competition in 2005 and ran until 2006. Different tasks (CryptoChallenges, CC) have been set of increasing difficulty, such as, for example, decrypting an encrypted message or forging a digital signature. The variety of topics covered by the collection of challenges was intended to provide a survey of modern cryptology.

Cipher challenges on four levels:

Level I Challenges - Pen & Paper

Level I challenges are similar to crossword puzzles from newspapers and can be solved with little cryptographic background. You might not even need a computer for solving level I challenges — all you need is a bit of clever thinking and probably a pen and paper. A program like CrypTool applied to a level I challenge can help reveal the answer to a level I challenge within minutes or even seconds, if the necessary algorithms are already built in. Hence, if you are new to cryptography, but nonetheless interested in the mysterious topic of cryptanalysis, give the level I challenges a try. You will almost assuredly meet quickly with success.

Level II Challenges - Programming skills required

Level II challenges require some background knowledge in cryptology and usually some computational power. Additionally, you may require tools that are not available in a convenient package like CrypTool, OpenSSL or SAGE. Therefore, you must first thoroughly understand the problem and then you may need to write a computer program, which helps you. It could take hours or even days to solve a level II challenge. Hence, if you consider yourself well-armed with cryptologic knowledge (such as if you are a university student in a cryptographic course), give the level II challenges a try. Success may not come easily, but it will be a worthwhile endeavor.

Level III Challenges - Extensive computing power recommended

Level III challenges require a thorough background in cryptanalysis and usually significant computational power as well. The problems in this level represent current research topics that are believed to be very difficult to solve. Thus, practical solutions may not even exist and ready-to-run tools almost certainly do not. The methodology to solve some of these challenges may already be known, but it may require such a huge amount of computational power that only a large group of people working together in a distributed system could obtain the solution. Challenges in this category mark the thin line between algorithms that are still secure and those that are not. Solving them may take weeks or even several months. Hence, challenges in this level are intended for entire research groups with many experts in cryptanalysis, programming, and distributed systems. Success cannot be guaranteed, but if you are the first to successfully solve one of these challenges, it probably would catch the attention of the scientific community. Of course, it still remains up to you to publish or present any such scientific techniques and results.

Level X Challenges - Unsolved ciphers

Most level X challenges contain problems that have remained unsolved for a long time. The fact that they have been unsolved regardless of numerous attempts suggests these challenges being hard. However, a simple idea can probably reduce the difficulty of it to a simple level I challenge — currently it is just unknown if and how they can be solved. Of course such a challenge cannot be solved with a simple codeword, since even we (the respective author and the MTC3 team) do not know the solution (the plaintext, the original message or the approach). So if you discover a promising solution you should either contact the author or the MTC3 team. Furthermore, you can publish your findings in a scientific journal such as Cryptologia or Journal of Cryptology.

Have fun: https://www.mysterytwisterc3.org/en/