A recent paper of Farha et al. suggested an entity authentication scheme suitable for low-resource IoT edge devices, which relies on SRAM-based physically unclonable functions (PUFs). In this paper we analyze this scheme. We show that, while it claims to offer strong PUF functionality, the scheme creates only a weak PUF: an active attacker can completely read out the secret PUF response of the edge device after a very small amount of queries, converting the scheme into a weak PUF scheme which can then be counterfeited easily. After analyzing the scheme, we propose an alternative construction for an authentication method based on SRAM-PUF which better protects the secret SRAM startup state.
Category / Keywords: implementation / IOT, PUF Date: received 3 Mar 2022, last revised 3 Mar 2022 Contact author: yos at bgu ac il Available format(s): PDF | BibTeX Citation Version: 20220307:123950 (All versions of this report) Short URL: ia.cr/2022/292