# A One-way Secret Key Agreement with Security Against Active Adversaries

## TL;DR

This paper introduces an efficient one-way secret key agreement protocol that remains secure even when an active adversary can tamper with the communication, utilizing a specially designed secure MAC.

## Contribution

It extends existing OW-SKA protocols to active adversaries by integrating a secure MAC, ensuring robustness and secrecy against tampering.

## Key findings

- Protocol achieves security against active adversaries.
- Secrecy of the shared key is formally proven.
- The protocol is efficient and practical.

## Abstract

In a one-way secret key agreement (OW-SKA) protocol in source model, Alice and Bob have private samples of two correlated variables X and Y that are partially leaked to Eve through Z, and use a single message from Alice to Bob to obtain a secret shared key. We propose an efficient secure OW-SKA when the sent message can be tampered with by an active adversary. The construction follows the approach of an existing OW-SKA with security against passive adversaries, and uses a specially designed secure Message Authentication Code (MAC) that is secure when the key is partially leaked, to achieve security against active adversaries. We prove the secrecy of the established key and robustness of the protocol, and discuss our results.