This paper presents Veritas-PUF, a novel solution based on Physical Unclonable Functions to counter non-invasive physical tampering attacks. This includes localized X-Ray irradiation techniques that can alter circuit behavior without modifying data, directly impacting side-channel leakages. These emerging threats pose significant challenges for secure circuits. To address such attacks, we propose leveraging a ring oscillator PUF to generate a unique identifier sensitive to ionizing radiations. The inherent entropy generated by the device’s physical properties ensures that any alterations will be reflected in the PUF response, providing a robust detection mechanism against these types of attacks. Our experimental results show that with only three reliable challenge-response pairs, we achieve over 95% detection rate for X-ray tampering.

In this paper, we propose a novel approach that utilizes localized X-ray irradiation to amplify data-dependent leakage currents in CMOS-based cryptography circuits. Our proposed technique strategically targets specific regions in a circuit using X-rays, inducing variations in dynamic and static power consumption due to Total Ionizing Dose (TID) effects, which increases or even reveals hidden data leakage. In this work, we present several experimental campaigns highlighting the benefits of our approach to combinational and sequential logic. Our experiments show a significant increase in information leakage in the targeted regions, which improves the signal-to-noise ratio coefficient and thus makes recovering the processed bytes easier. We envision the possibility of using this technique on full cryptographic designs on both FPGA and ASICs.

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