Leveraging Self-Sovereign Identity, Blockchain, and Zero-Knowledge Proof to Build a Privacy-Preserving Vaccination Pass

TL;DR

This paper proposes a privacy-preserving vaccination pass using self-sovereign identity, blockchain, and zero-knowledge proofs, enabling users to prove vaccination status without revealing personal identity.

Contribution

It introduces a novel architecture combining these technologies to enhance privacy in health pass systems, with a working prototype demonstrating feasibility.

Findings

Effective proof of vaccination without identity disclosure

Flexible, modular architecture for health pass systems

Prototype validates practical implementation

Abstract

The current humanitarian health crisis popularized the debate on data privacy. At the same time, several cities, states, and even countries put the mandatory presentation of health pass to access services into practice. In this article, we explore the concepts of self-sovereign identity, blockchain, and zero-knowledge proofs to propose a solution to the problem of presenting proof of vaccination. This solution allows users to prove that they are vaccinated for different pathogens without revealing their identity. The architecture is loosely coupled, allowing components to be exchanged, which we discuss when we present the implementation of a working prototype.