An algorithm submitted to the NIST post-quantum encryption competition – and one that made it to the fourth round – has been defeated. The algorithm, Supersingular Isogeny Key Encapsulation (SIKE), was broken by Wouter Castryck and Thomas Decru at KU Leuven, and the process described in a paper written at the end of July 2022.

Cryptographers are not surprised by such an event; but security leaders concerned about their ability to protect secrets after the arrival of quantum computers, need to consider the implications.

Reposted from Security Week.