The (in)security of some recently proposed lightweight key distribution schemes

Abstract

Two recently published papers propose some very simple key distribution schemes designed to enable two or more parties to establish a shared secret key with the aid of a third party. Unfortunately, as we show, most of the schemes are inherently insecure and all are incompletely specified - moreover, claims that the schemes are inherently lightweight are shown to be highly misleading. We also briefly critique a somewhat related very recent paper by the same authors that uses similar techniques to achieve what are claimed to be secure multiparty computations.