1970-01-01

(2026-02) Non Interactive MPC, (Quantumly) Revisited

• [[Prabhanjan Ananth]]
• [[Divyanshu Bhardwaj]]
• [[Aparna Gupte]]

2026-02-18

• #cryptography
• #paper

Abstract

Classical non-interactive secure computation, despite being extensively studied, suffers from an inherent barrier: adversaries can learn the entire residual function via resetting attacks. We investigate whether quantum resources can circumvent this barrier and restrict adversarial leakage. Our results are as follows:

1. $\textbf{Definitions}$: We introduce new security definitions for the one-message MPC and 2PC settings that restrict the amount of adversarial leakage compared to prior classical definitions.
2. $\textbf{MPC}$: There exist information-theoretically secure one-message multi-party computation protocols in the oracle model in both the quantum pre-processing and classical pre-processing settings.
3. $\textbf{2PC}$: There exist semi-honest secure one-message two-party computation for (randomized) pseudorandom functionalities in the plain model based on LWE and maliciously secure one-message two-party computation for (randomized) constrained functionalities in the CRS model based on iO. Prior work by [Gupte, Liu, Raizes, Roberts and, Vaikuntanathan STOC 2025] achieved semi-honest security based on iO.

Our results demonstrate the power of quantum information to circumvent barriers in classical secure computation.