Attached is the security report for R5, the POW problem for Nebula. I had to give an account on the security of Nebula since Nebula employs new kinds of cryptosystems which have not been implemented in practice so far. Keep in mind that it is ill-advised to employ a new symmetric cryptosystem in practice as soon as it is developed. It typically takes a couple of years for people to thoroughly investigate a new symmetric cryptosystem before it is employed in practice, and for public key cryptosystems it takes much longer. However, by the nature of R5, a security report that should be sufficient to ensure the security of R5 since it is much more difficult for something to go wrong with R5 that it is for something to go wrong with a symmetric cryptosystem such as a hash function.
I will at one point release an updated version of the security report for R5 since there is information about R5 which I do not want to reveal publicly at the moment (I apologize for my violation of Kerckhoffs’s principle.Don’t worry. All information about R5 will be openly available soon enough though. And my violation for Kerckoff’s principle are not for cryptographic security reasons but instead for logistical reasons).