Voting Privacy

Duration: NaN:NaN:NaN

Speaker: Dani Vilardell

Type: Talk

Expertise: No prior knowledge

Event: Devcon

Date: Nov 2026

In 2025, a buyer paid 5 ETH on LobbyFi to control $6.5M worth of ARB votes, and this is one of many incidents. On-chain governance has made vote buying and coercion practical, yet most DAO voting today is fully public; and even where ballots are hidden, privacy is weaker than it looks. This talk digs into voting privacy: what ballot secrecy, receipt-freeness, and coercion resistance actually mean, why coercion resistance matters for any election with real stakes, and why the classical defenses from the e-voting literature rest on assumptions that fail in remote, blockchain-based settings. We then turn to a threat unique to token-weighted voting: analyzing thousands of proposals across 30+ DAOs, we find that published tallies alone often reveal how individuals voted, even with secret ballots. This talk draws on two recent research results from the speaker (Cast Iron and B-Privacy, USENIX Security '26), a Cornell PhD researcher.