June 17, 2016
The DAO exploited on Ethereum
An attacker drained roughly $60 million from The DAO on June 17, 2016 — exploiting a recursive-call bug in the largest Ethereum smart contractPrograms on a blockchain that run automatically when conditions are met — used in DeFi and NFTs. crowdfunding project to date.
What it was for
The DAO had raised ether through a novel on-chain venture fund; the hack forced a contentious hard fork that split Ethereum and Ethereum Classic. Audits, formal verification, and multisig treasuries became standard after developers saw immutable code fail in production.
Why it's here
The DAO hack was smart-contract security's Lehman moment.
Why it mattered
It proved on-chain code needed audits and governance escape hatches.
What it solved
Nothing yet — it exposed that immutable contracts could lose millions from a single logic bug.
Media
- ImageThe DAO (organization)
GitR0n1n, Public domain, via Wikimedia Commons
Related
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- Ethereum Merge completesSeptember 15, 2022
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