Vesselin Velichkov, Open Zeppelin: ZK Proofs for Blockchain Applications: an Auditor's Perspective

Thu, Oct 2, 2025, 12:00 AM

In this talk from ETHSofia 2024, Vesselin introduces the concept of zero-knowledge proofs (ZKPs) and describes their use in blockchain applications with a focus on security risks. He highlights several selected ZKP vulnerabilities found in audits and shares auditing guidelines and best practices, based on our own experience. Vesselin Velichkov is a ZK cryptography researcher at OpenZeppelin, where he is performing ZK research and audits of ZK implementations. Before joining OpenZeppelin he was a cryptography engineer at two Web3 start-ups and a lecturer in security and privacy at the University of Edinburgh. Vesselin holds a PhD in cryptography from KU Leuven, Belgium and is a co-designer of the ZK-friendly hash function Anemoi. Chapters: 00:00 Introduction to Zero Knowledge Proofs in Blockchain 00:42 Overview of Open Zeppelin and ZKP Auditing 01:15 Motivation for ZK Proofs in Blockchain 01:47 Scalability and Privacy Challenges 02:16 Historical Context of Zero Knowledge Proofs 02:46 Practical Examples of ZK Proofs 04:28 Interactive vs. Non-Interactive ZK Protocols 08:06 Scalability with ZK Rollups 11:38 Privacy via ZK Proofs - Aztec Network Example 13:55 Common Vulnerabilities in ZK Proof Implementations 14:32 Systematic Analysis of ZKP Vulnerabilities 15:35 Case Studies of ZKP Vulnerabilities 19:26 Challenges and Future of ZKP Auditing 20:30 Best Practices for ZKP Auditors and Implementers Connect with Vesselin: LinkedIn: linkedin.com/in/vesselin-velichkov Twitter: https://x.com/vesselinux This video was recorded during the ETHSofia Conference and Hackathon - October 17-19, 2024. ETHSofia is THE crypto tech conference in Sofia, Bulgaria, bringing together enthusiasts, developers, researchers, and academia focused on Ethereum and other L1 chains. The conference is supported by the Ethereum Foundation and made possible by the generous contributions of industry leaders. For more information, please visit: https://www.ethsofia.com/ 🌍Join the community: X (Twitter): https://x.com/ETHSofiaBG Telegram: https://t.me/+_i70pgfFHjBkMjZk LinkedIn: @/ethsofia/ #OpenZeppelin #ZKProofs #ZKaudit #VesselinVelichkov #Audit #Web3Audit