Cryptanalysis of Composite PUFs (Extended abstract-invited talk)

In recent years, Physcially Unclonable Functions (PUFs) have become important cryptographic primitive and are used in secure systems to resist physical attacks. Since PUFs have many useful properties such as memory-leakage resilience, unclonablity, tampering-resistance, PUF has drawn great interest in academia as well as industry. As extremely useful hardware security primitives, PUFs are used in various proposed applications such as device authentication and identification, random number generation, and intellectual property protection. One of important requirement to PUFs is that PUFs should have small hardware overhead in order to be utilized in lightweight application such as RFID. To achieve this goal, Composite PUFs are developed and introduced in RECONFIG2013 and HOST2014. In a nutshell, Composite PUFs are built by using many small PUFs primitives. In this talk, we show that Composite PUFs introduced in RECONFIG2013 are not secure by presenting its cryptanalysis.