Horizontal Address-Bit DEMA against ECDSA

With the advent of the Internet of Things security features become more and more important. Especially data integrity and authentication of its origin are of utmost importance. Digital signatures are a well-known means to provide these features. In this paper we detail our horizontal DEMA attack against a hardware implementation of the Montgomery kP algorithm for the NIST elliptic curve B-233. We apply the attack successfully against the ECDSA algorithm. In the past vertical attacks exploiting the key dependable activity of the bus and addressing of registers have been published. In contrast to those attacks we performed a horizontal attack exploiting the same phenomena using a single trace of electromagnetic emanations.