On the Sixth International Olympiad in Cryptography NSUCRYPTO

Abstract

NSUCRYPTO is the unique cryptographic Olympiad containing scientific mathematicalproblems for professionals, school and university students from any country. Its aim is to involveyoung researchers in solving curious and tough scientific problems of modern cryptography. Fromthe very beginning, the concept of the Olympiad was not to focus on solving olympic tasks but onincluding unsolved research problems at the intersection of mathematics and cryptography. TheOlympiad history starts in 2014. In 2019, it was held for the sixth time. We present the problemsand their solutions of the Sixth International Olympiad in cryptography NSUCRYPTO$$^{\prime}$$2019. Under consideration are the problems relatedto attacks on ciphers and hash functions, protocols, Boolean functions, Dickson polynomials, primenumbers, rotor machines, etc. We discuss several open problems on mathematical countermeasuresto side-channel attacks, APN involutions, S-boxes, etc. The problem of finding a collision for thehash function Curl27 was partiallysolved during the Olympiad.