ZK/SEC Research notes from zkSecurity
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Proof is in the Pudding · Part 8 of 10

Archetype x zkSecurity - Proof is in the Pudding: Privacy in Payment Networks

For the 8th session of Proof is in the Pudding, we teamed up with Archetype to explore the fascinating world of privacy in payment networks.

There's no single best approach to privacy, but there's no shortage of interesting techniques that have been developed over the years to break linkability, hide addresses, and obscure transaction data. In this session, we take a comprehensive tour through the evolution of private payment systems, covering E-Cash, blind signatures, Bitcoin privacy, confidential transactions and Pedersen commitments, Mimblewimble, Monero, stealth addresses, ring signatures, MobileCoin and TEEs, Zcash, and Zether.

If you enjoy this video, check out our previous episodes:

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The Year Finding and Exploiting Bugs Became Cheap, and What to Do About It

The economics of security have changed. AI has made finding and exploiting bugs cheaper, including in cryptographic and zero-knowledge code, while validation and remediation remain slow. Here is our view of what happened, what comes next, and how teams should change the way they secure their stack to defend against AI-assisted attackers.

Stefanos Chaliasos · September 07, 2026

Variants of KZG: Part V, Multilinear Commitments with Mercury

In this final post of the series, we extend univariate KZG commitments to multilinear polynomials through Mercury. Building on Gemini, we fold half of the variables at once, use polynomial division to bind this large fold to the original commitment and reduce the remaining multilinear evaluations to a batched inner product check. We then walk through the end-to-end opening protocol. We conclude by examining its proof size, prover cost and verifier cost.

Varun Thakore · August 17, 2026

Variants of KZG: Part IV, Multilinear Commitments with Gemini

In this blog post, we extend univariate KZG commitments to multilinear polynomials through Gemini. We introduce recursive partial evaluations, derive the split-and-fold identity and express each fold as a univariate identity that can be checked using KZG openings. We then walk through the end-to-end opening protocol. We conclude by examining its proof size, prover cost, and verifier cost.

Varun Thakore · August 12, 2026
Recommended

Archetype x zkSecurity - Proof is in the Pudding: The Other Dark Forest (Offchain Public Keys)

In Session 07 of "Proof is in the Pudding," we explore the other dark forest, the realm of offchain public keys. We dive into zkLogin, ZK Email, and ZKPassport, examining how these protocols handle authentication and privacy. We also discuss the issue of unlinkability in privacy protocols and why replacing traditional signature verifications with zero-knowledge proofs could unlock more interesting and powerful ZK products.

ZK/SEC · October 21, 2025

Archetype x zkSecurity - Proof in the Pudding: Introduction to Data Availability (Sampling)

In the latest "Proof is in the Pudding" session, we team up with Archetype to break down the essentials of Data Availability Sampling. We dive into how rollups and Ethereum's DA system work, explore the role of DA chains, and touch on the basics of verifiable sharding. This introduction is perfect for anyone curious about the foundations of data availability sampling and how these concepts are playing out in the blockchain world.

ZK/SEC · October 02, 2025

Archetype x zkSecurity (Whiteboard Session) - Proof is in the Pudding: How to prove false statements

In our third whiteboard session with Archetype, we dive into the fascinating world of cryptographic protocols by breaking down the intricacies of the Fiat-Shamir security model and the GKR protocol. Whether you're a cryptography enthusiast or just curious about how these complex mechanisms enhance security, this is a chance to explore the theories with us in a friendly and digestible way. Don't miss the opportunity to expand your understanding of this cutting-edge topic!

ZK/SEC · February 25, 2025
More to explore

Uncovering the Phantom Challenge Soundness Bug in Solana's ZK ElGamal Proof Program

In June 2025, we uncovered a serious soundness issue in Solana's ZK ElGamal Proof Program that could let attackers manipulate confidential token transfers undetected. We worked with the Anza team to quickly address the flaw by pausing and disabling vulnerable components. This post dives into the root cause, which was a subtle mistake in handling prover-generated challenges within sigma OR proofs, revealing broader lessons in zero-knowledge protocol security. If you're interested in cryptographic protocol design, this could provide valuable insights.

Suneal Gong · June 26, 2025

zkBitcoin: Use Zero-Knowledge Applications (zkapps) on Bitcoin

We're excited to introduce zkBitcoin, a new tool that lets you create zero-knowledge applications on Bitcoin using a minimal layer 2 protocol. This innovation opens up a world of complex, privacy-focused apps by enhancing Bitcoin's scripting capabilities. We're currently on testnet, so you can jump in and explore the possibilities. Check out our whitepaper or watch some videos for a deeper dive. It's an exciting time for Bitcoin development, and we can't wait to see what you'll build!

David Wong · January 31, 2024

Groth16, Intuitively

Groth16 is still the gold standard for succinct SNARKs: 128-byte proofs, constant-size verification, and a decade of real-world deployment. But despite its ubiquity, almost nobody explains *why* it works the way it does. In this post, we build Groth16 from the ground up, starting from R1CS and QAPs, then layer in pairings, trusted setup parameters, and the separator tricks (α, β, γ, δ) that make the scheme sound. By the end, you should have an intuitive grasp of every term in the final verifier equation.

David Wong · May 01, 2026