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Not AvailablePhysically Unclonable Functions (PUFs) are emerging lightweight hardware security primitives that utilize inherent manufacturing variations in integrated circuits to generate unique and reproducible digital fingerprints for authorization or authentication. This paper explores the implementation and evaluation of SRAM-based PUFs on the ESP32 microcontroller under normal and fault-injected operating conditions. A baseline PUF generation method is done, and its reliability and stability are evaluated using the intra-hamming distance. Fault injection attacks using voltage anomalies are employed to study the effects on the PUF’s reliability. Preliminary results show that while the PUF is stable under normal operating conditions, the reliability significantly decreases under faulted conditions. The results showcase the vulnerability of SRAM PUFs to environmental and operational factors and lay the groundwork for exploring additional fault injection methods and countermeasures for enhanced robustness.
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Quantitative Fault Injection Analysis
Active fault injection is a credible threat to real-world digital systems computing on sensitive data. Arguing about security in the presence of faults is non-trivial, and state-of-the-art criteria are overly conservative and lack the ability of fine-grained comparison. However, comparing two alternative implementations for their security is required to find a satisfying compromise between security and performance. In addition, the comparison of alternative fault scenarios can help optimize the implementation of effective countermeasures. In this work, we use quantitative information flow analysis to establish a vulnerability metric for hardware circuits under fault injection that measures the severity of an attack in terms of information leakage. Potential use cases range from comparing implementations with respect to their vulnerability to specific fault scenarios to optimizing countermeasures. We automate the computation of our metric by integrating it into a state-of-the-art evaluation tool for physical attacks and provide new insights into the security under an active fault attacker.
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- Award ID(s):
- 2219810
- PAR ID:
- 10515000
- Editor(s):
- Guo, J; Steinfeld, R
- Publisher / Repository:
- Springer Lecture Notes in Computer Science 14441
- Date Published:
- Journal Name:
- Advances in Cryptology – ASIACRYPT 2023
- Format(s):
- Medium: X
- Location:
- Singapore
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.1007/978-981-99-8730-6_10
