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Abstract and Figures

Physical Unclonable Functions (PUFs) are vulnerable to machine learning modeling attacks that can predict their responses. To counter this threat, we introduce Obfuscated PUF (OPUF), a novel PUF design that employs advanced obfuscation techniques to enhance security. OPUF significantly outperforms existing PUFs in terms of resistance to machine learning attacks, including logistic regression (LR) and multilayer perceptron (MLP). It achieves a 50.69% and 49.54% accuracy reduction in LR and MLP attacks, respectively, compared to the best-performing existing PUFs. Moreover, OPUF maintains excellent quality metrics, with 50% uniqueness and 50.15% uniformity, demonstrating its inherent randomness and unpredictability. OPUF achieves its enhanced security through a multi-layered architecture that incorporates obfuscation techniques and nonlinear properties. By introducing internal challenges that are difficult for attackers to access, OPUF effectively thwarts modeling attempts. Our experimental results demonstrate OPUF’s superior performance in resisting various machine learning attacks, even when faced with extensive training data. OPUF offers a promising solution for secure hardware implementations, addressing the critical need for PUFs that can withstand the challenges posed by modern machine learning attacks.
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OPUF: Obfuscated PUF against Machine Learning
Modeling Attacks
Mostafa Moghaddas
*
and Marziye Pandi
School of Computer Engineering,
Iran University of Science and Technology,
Tehran, Iran
*
m_moghaddas@alumni.iust.ac.ir
m_pandi@alumni.iust.ac.ir
Hakem Beitollahi
School of Computer Engineering,
Iran University of Science and Technology,
Tehran, Iran
Department of Computer Science, Soran University,
Soran, Kurdistan Region, Iraq
hakem.beitollahi@soran.edu.iq
Received 16 April 2024
Accepted 27 January 2025
Published 29 April 2025
Physical Unclonable Functions (PUFs) are vulnerable to machine learning modeling attacks
that can predict their responses. To counter this threat, we introduce Obfuscated PUF (OPUF),
a novel PUF design that employs advanced obfuscation techniques to enhance security. OPUF
signi¯cantly outperforms existing PUFs in terms of resistance to machine learning attacks,
including logistic regression (LR) and multilayer perceptron (MLP). It achieves a 50.69% and
49.54% accuracy reduction in LR and MLP attacks, respectively, compared to the best-per-
forming existing PUFs. Moreover, OPUF maintains excellent quality metrics, with 50%
uniqueness and 50.15% uniformity, demonstrating its inherent randomness and unpredict-
ability. OPUF achieves its enhanced security through a multi-layered architecture that incor-
porates obfuscation techniques and nonlinear properties. By introducing internal challenges
that are di±cult for attackers to access, OPUF e®ectively thwarts modeling attempts. Our
experimental results demonstrate OPUF's superior performance in resisting various machine
learning attacks, even when faced with extensive training data. OPUF o®ers a promising
solution for secure hardware implementations, addressing the critical need for PUFs that can
withstand the challenges posed by modern machine learning attacks.
Keywords: Hardware security; physical unclonable function; machine learning; lightweight
encryption; PUF obfuscation.
Corresponding author.
Journal of Circuits, Systems, and Computers
(2025) 2550245 (20 pages)
#
.
cWorld Scienti¯c Publishing Company
DOI: 10.1142/S0218126625502457
2550245-1
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