Cryptology ePrint Archive: Report 2019/1443

CAS-Unlock: Unlocking CAS-Lock without Access to a Reverse-Engineered Netlist

Abhrajit Sengupta and Ozgur Sinanoglu

Abstract: CAS-Lock (cascaded locking) is a SAT-resilient locking technique, which can simultaneously thwart SAT and bypass attack, while maintaining non-trivial output corruptibility. Despite all of its theoretical guarantees, in this report we expose a serious flaw in its design that can be exploited to break CAS-Lock. Further, this attack neither requires access to a reverse-engineered netlist, nor it requires a working oracle with the correct key loaded onto the chip's memory. We demonstrate that we can activate any CAS-Locked IC without knowing the secret key.

Category / Keywords: implementation / Hardware security, IP piracy, Logic locking

Date: received 11 Dec 2019, last revised 11 Dec 2019

Contact author: as9397 at nyu edu

Available format(s): PDF | BibTeX Citation

Version: 20191212:085631 (All versions of this report)

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