Double Seminar: Vasilios Mavroudis & Jonathan Bootle

<br>We will have a double seminar this week with two shorter presentations by Vasilios Mavroudis &amp; Jonathan Bootle. <br><br>Vasilios Mavroudis -- High-Assurance Cryptographic Hardware from Untrusted Components<br><br>Abstract:<br>The semiconductor industry is fully globalized and integrated circuits (ICs) are commonly defined, designed and fabricated in different premises across the world. This reduces production costs, but also exposes ICs to supply chain attacks, where insiders introduce malicious circuitry into the final products. Additionally, despite extensive post-fabrication testing, it is not uncommon for ICs with subtle fabrication errors to make it into production systems. While many systems may be able to tolerate a few byzantine components, this is not the case for cryptographic hardware, storing and computing on confidential data. For this reason, many error and backdoor detection techniques have been proposed over the years. So far all attempts have been either quickly circumvented, or come with unrealistically high manufacturing costs and complexity.<br><br>In this talk, we will present a practical high-assurance architecture that uses commercial off-the-shelf (COTS) hardware, and provides strong security guarantees, even in the presence of multiple malicious or faulty components. The key idea is to combine protective-redundancy with modern threshold cryptographic techniques to build a system tolerant to hardware trojans and errors. We will also demonstrate our Hardware Security Module that provides the highest level of assurance possible with COTS components. Specifically, we employ more than a hundred COTS secure crypto-coprocessors, verified to FIPS140-2 Level 4 tamper-resistance standards, and use them to realize high-confidentiality random number generation, key derivation, public key decryption and signing. Our experiments show a reasonable computational overhead (less than 1% for both Decryption and Signing) and an exponential increase in backdoor-tolerance as more ICs are added. This talk is based on our CCS 2017 paper and the project website is: <a href=";sa=... Mavroudis is a Doctoral Researcher in the Information Security Group at University College London, where he studies the security and privacy aspects of digital ecosystems with a focus on emerging technologies and previously unknown attack vectors. In cooperation with industrial partners, he recently released a prototype of a high-assurance cryptographic hardware architecture that maintains its security properties even in the presence of malicious hardware components. Moreover, his study on ultrasound tracking received wide-spread attention and is considered the seminal work on the security of that ecosystem.<br><br><br>Jonathan Bootle -- Cryptanalysis of Compact-LWE<br><br>Abstract:<br>As an invited speaker of the ACISP conference held in July 2017, Dongxi Liu introduced a new lattice-based encryption scheme (joint work with Li, Kim and Nepal) designed for lightweight IoT applications. The scheme, which has been submitted to the NIST postquantum competition, is based on a variant of standard LWE called Compact-LWE, but is claimed to achieve high security levels in considerably smaller dimensions than usual lattice-based schemes. In our paper, we show, for the proposed parameters, that ciphertexts in the new encryption scheme can be decrypted using the public key alone, and given the public key, how to recover a functional secret key which can be used to correctly decrypt ciphertexts with 100%. Furthermore, even setting aside parameter choices, our results show that the ways in which Compact-LWE departs from usual LWE-based encryption schemes do not appear to enhance security in a meaningful way.<br><br>Bio:<br>I am a PhD candidate in the area of cryptography, working under the supervision of Dr Jens Groth and Dr Sarah Meiklejohn. I am currently working on efficient zero-knowledge proofs. More specifically, I am looking at zero-knowledge membership proofs. I am also interested in lattices and post-quantum cryptography.<br><a href="">

Thursday, April 19, 2018 - 4:15pm to 5:15pm
Gates 415