[Paper Review] A Blockchain-based Electronic Voting System: EtherVote

Achilleas Spanos, Ioanna Kantzavelou|arXiv (Cornell University)|Jul 20, 2023

Internet Traffic Analysis and Secure E-votingComputer Science3 citations

TL;DR

This paper proposes EtherVote, a blockchain-based electronic voting system built on the Ethereum blockchain using smart contracts to ensure vote immutability, privacy, and verifiability. It enables secure, decentralized voter identification via Metamask wallets and encrypted personal data, with OTP-based authentication via SMS to prevent double voting, offering a scalable, transparent, and fraud-resistant solution for national elections.

ABSTRACT

The development of an electronic voting system that would replace traditional election procedures is a research topic of great interest for many years. Blockchain technology could provide some guarantees and fulfill strong requirements for electronic voting platforms, such as transparency, immutability, and confidentiality. From time to time research is conducted to address problems in voting systems. Many research works attempt to implement secure and reliable voting systems, which address known security, anonymity, and fraud issues that might threaten such systems. This paper presents a proposal of a secure electronic voting system, the EtherVote, using the Ethereum Blockchain network that focuses deeply on the field of identification of eligible citizens. The proposed system will be entirely based on Blockchain without any central authority servers or databases, thus improving security, privacy, and election cost. Limitations, problems, and solutions are discussed, in order to make the proposed electronic voting system ideal and ready to use for national elections.

Motivation & Objective

• To design a decentralized electronic voting system that eliminates reliance on central authorities or databases.
• To ensure voter anonymity, vote integrity, and immutability using Ethereum blockchain and smart contracts.
• To solve the critical challenge of secure, decentralized voter identification without storing personal data in plaintext.
• To implement a multi-factor authentication process combining Metamask login and OTP via SMS for vote binding and anti-replay protection.
• To enable citizens to verify their vote using transaction hashes, enhancing transparency and trust in the electoral process.

Proposed method

• The system uses Ethereum smart contracts to store voter eligibility lists and manage voting logic without centralized servers.
• Eligible voters register by linking their Metamask address to encrypted personal data (ID, name, phone) using SHA256 hashing.
• On election day, voters authenticate via Metamask password and re-enter personal data, which is re-hashed and matched to the stored hash for verification.
• Upon successful dual authentication, a time-limited one-time password (OTP) is generated and sent via SMS to the voter’s registered number.
• Voting is performed by submitting the OTP along with the candidate choice, which triggers a transaction that increments the candidate’s vote count and locks the voter’s address to prevent multiple votes.
• All transactions, including OTP creation and vote submission, are recorded on the public Ethereum blockchain for auditability while keeping personal data encrypted and private.

Experimental results

Research questions

• RQ1 How can a fully decentralized electronic voting system be designed without relying on central authorities or databases?
• RQ2 How can voter identity be securely authenticated in a blockchain-based system while preserving anonymity and preventing double voting?
• RQ3 What mechanisms can ensure vote immutability and verifiability without exposing personal data or vote content?
• RQ4 How can external data (e.g., OTP delivery via SMS) be securely integrated into smart contracts, given their lack of native API access?
• RQ5 To what extent can cryptographic hashing and smart contract logic ensure both privacy and auditability in electronic voting?

Key findings

• The EtherVote system successfully implements a fully decentralized electronic voting mechanism using Ethereum smart contracts, eliminating the need for centralized databases or servers.
• The use of SHA256-hashed personal data stored as key-value pairs on the blockchain ensures that sensitive information remains private while enabling secure voter identification.
• The dual-factor authentication process—Metamask login and re-verification of personal data—effectively prevents unauthorized voting and ensures that only eligible voters can cast a ballot.
• The OTP mechanism, delivered via SMS and time-limited, successfully prevents replay attacks and ensures that each vote is uniquely tied to a single authentication session.
• The system prevents double voting by marking a voter’s address as locked after a successful vote submission, with the state change enforced by the smart contract.
• The system enables public verification of votes through transaction hashes, allowing voters to confirm their vote was recorded without revealing its content, thus enhancing transparency and trust.