Design for the Compromised Signer: Bounding Blast Radius in Smart Accounts

Since 2024, over $2B has been stolen from multisig-secured organizations — Bybit ($1.4B), WazirX, DMM, Radiant. No keys were stolen; no multisig math was broken. In every case the signer's screen lied: the approved payload wasn't the displayed one. More signers didn't help. Better signing UX didn't help.

The one layer those attackers couldn't touch is onchain enforcement at the account itself. In 5 minutes I'll share a mental model for designing it, from building smart account policy enforcement in production: two composable primitives — execution scoping (who can act, within what bounds) and universal guards (what the account may ever do) — plus the rule that decides whether a policy is real or theater: policy must protect itself. If reconfiguration outpaces your transaction delay (Beanstalk, $182M), you built decoration, not defense.

Speakers: Dev Pramoth

Track: Security