Web3 Security & Cryptography Blog

Deep dives into smart contract audits, zero-knowledge proofs,
and advanced Web3 security concepts by the Hexens team.

Understanding Differential Privacy: Part 2

AI

Understanding Differential Privacy: Part 2

A hands-on guide to DP-SGD: how it works, how VaultGemma uses it at LLM scale, and what private vs non-private training actually costs on ...

Understanding Differential Privacy: Part 1

AI

Understanding Differential Privacy: Part 1

A practical guide to differential privacy: the attacks that motivate it, the formal definition, trust models, mechanisms, and privacy accoun...

Gröbner Bases in Cryptanalysis Part2: Attacking Poseidon

Cryptography

Gröbner Bases in Cryptanalysis Part2: Attacking Poseidon

Learn how Gröbner bases break cryptographic hash functions. We attack a reduced-round Poseidon instance, recovering a preimage from its dige...

Gröbner Bases in Cryptanalysis Part 1: The Underlying Algebra

Cryptography

Gröbner Bases in Cryptanalysis Part 1: The Underlying Algebra

This post develops the full algebraic machinery, covering polynomial rings, ideals, monomial orderings, and Buchberger's algorithm, and demo...

Encrypted Vector Databases Without Sacrificing Search

AI

Encrypted Vector Databases Without Sacrificing Search

A technical deep-dive into cryptographically secure vector databases, covering embedding attacks, why exact distance-preserving encryption f...

Secure Federated Learning with Cryptography

AI

Secure Federated Learning with Cryptography

Federated learning promises privacy by keeping data local, yet model updates remain vulnerable to inference and poisoning attacks. This arti...

Attacks on Threshold Schemes: Part 2

Security

Attacks on Threshold Schemes: Part 2

Deep dive into protocol-level vulnerabilities in threshold signature schemes: MtA oracle attacks, reshare synchronization flaws, determinist...

Attacks on Threshold Schemes: Part 1

Security

Attacks on Threshold Schemes: Part 1

A technical guide to real-world attacks on threshold signature schemes. Explore implementation bugs like missing checks and proofs, wrong pa...

Constructing and Breaking SIDH

Cryptography

Constructing and Breaking SIDH

Explore a detailed, hands-on walkthrough of supersingular isogeny cryptography (SIDH), from elliptic curve preliminaries and kernel-based is...

A Comparison of zkVM DSLs: Halo2, Zirgen, and Plonky3

Zero Knowledge

A Comparison of zkVM DSLs: Halo2, Zirgen, and Plonky3

Deep dive into ZK constraint systems: Halo2's PLONKish circuits, Zirgen's STARK compiler, and Plonky3's direct AIR authoring. Complete with ...