EM analysis of a wireless Java-based PDA

Abstract

The susceptibility of wireless portable devices to electromagnetic (EM) attacks is largely unknown. If analysis of electromagnetic (EM) waves emanating from the wireless device during a cryptographic computation do leak sufficient information, it may be possible for an attacker to reconstruct the secret key. Possession of the secret cryptographic key would render all future wireless communications insecure and cause further potential problems, such as identity theft. Despite the complexities of a PDA wireless device, such as operating system events, interrupts, cache misses, and other interfering events, this article demonstrates that, for the first time, repeatable EM differential attacks are possible. The proposed differential analysis methodology involves precharacterization of the PDA device (thresholding and pattern recognition), and a new frequency-based differential analysis. Unlike previous research, the new methodology does not require perfect alignment of EM frames and is repeatable in the presence of a complex embedded system (including cache misses, operating system events, etc), thus supporting attacks on real embedded systems. This research is important for future wireless embedded systems, which will increasingly demand higher levels of security.