Attacking SRAM PUFs using very-low-temperature data remanence

In this work, we extend our previous manuscript regarding a systematic study of data remanence effects on an intrinsic Static Random Access Memory Physical Unclonable Function (SRAM PUF) implemented on a Commercial Off-The-Shelf (COTS) device in the temperature range between -110 degrees C and -40 degrees C. As the experimental results of our previous work show, an attack against intrinsic SRAM PUFs, which takes advantage of data remanence effects exhibited due to low temperatures, is possible, resulting in the attacker being able to know the PUF response, with high probability. As demonstrated in our previous work, this attack is highly resistant to memory erasure techniques and can be used to manipulate the cryptographic keys produced by the SRAM PUF. In this work, we examine and discuss potential countermeasures against this attack in more detail, and investigate whether this attack can be performed using an experimental setup that does not guarantee a high degree of thermal isolation. Additionally, we also examine and discuss whether very low temperatures can be used to perform another relevant type of attack against SRAM PUFs, based on whether very low temperature can prevent the SRAM from being overwritten. Finally, we also discuss related works and the generalisation of our results in more detail. (C) 2019 Elsevier B.V. All rights reserved.