Replay-resistant Few-shot Disk Authentication using Electromagnetic Fingerprint

External disks (henceforth referred to as disks) are commonly used data storage peripherals for hosts. Verifying the legitimacy of these disks is essential to mitigate security risks, such as privacy breaches and virus propagation, before initiating interactions with a host. To address this challenge, we propose DiskPrint, a novel replay-resistant, few-shot disk authentication system that relies on unintentional electromagnetic (EM) emanations from the internal components of disks. The core idea of DiskPrint is that EM signals emitted during data writing operations can reveal unique hardware discrepancies among different disks. Building on electromagnetic theory, we develop a theoretical model that links EM signals to the underlying electronic components of the disk, demonstrating the feasibility of extracting distinctive disk fingerprints from these emanations. We also propose a set of signal enhancement techniques aimed at mitigating EM interface noise and improving the signal-to-noise ratio (SNR) of the EM measurements. To further strengthen the security of DiskPrint, we introduce a device-agnostic, replay-resistant approach by incorporating randomness into the leaked EM signals. Real-world experiments with 60 disks, spanning both hard disk drives (HDDs) and solid-state drives (SSDs) from seven brands and 14 different models, indicate that DiskPrint achieves an authentication success rate exceeding 99.6% with only three registration samples. A robustness analysis confirms its stability over time, while a security evaluation shows its resilience against various attack scenarios.