ZKP Banking Interface: A Privacy-Preserving, Context-Aware Authentication System Using Zero-Knowledge Proofs

Abstract

Traditional banking systems rely on passwords, PINs, and centralized biometric storage, exposing users to phishing, SIM-swap attacks, and credential reuse vulnerabilities. This paper presents the ZKP Banking Interface, a pinless, context-aware financial authentication system built on Zero-Knowledge Proof (ZKP) technology. A unified ZK-SNARK circuit (Groth16), implemented in Circom, encodes three simultaneous security factors: identity commitment, trusted network context, and transaction threshold logic using Poseidon hashing. Conditional biometric and puzzle challenges are enforced cryptographically for higher-risk scenarios. Proof generation and verification are fully automated within the browser using snarkJS and WebAssembly artifacts, eliminating manual proof handling. The system supports two verification modes: local (device-only privacy) and on-chain (public auditability via a Solidity smart contract on a Hardhat network). Experimental evaluation across five test scenarios confirms correct contextual policy enforcement, successful proof validation in both modes, and a smooth, practical banking user experience. The proposed system demonstrates that ZKP-based authentication can replace traditional credentials while maintaining strong privacy guarantees.