Cryptanalysis of an Improved One-Way Hash Chain Self-Healing Group Key Distribution Scheme

In 2014, Chen et al. proposed a one-way hash self-healing group key distribution scheme for resource-constrained wireless networks in Journal of Sensors (14(14):24358-24380, DOI: 10.3390/ s141224358). They asserted that their scheme 2 has the constant storage overhead, low communication overhead, and is secure, i.e., achieves mt-revocation capability, mt-wise forward secrecy, any-wise backward secrecy and has mt-wise collusion attack resistance capability. Unfortunately, an attack method against Chen et al.’s scheme 2 is found in this paper, which contributes to some security flaws. More precisely, a revoked user can recover other legitimate users’ personal secrets, which directly breaks the forward security, mt-revocation capability and mt-wise collusion attack resistance capability. Thus, Chen et al.’s scheme 2 is insecure.