How can a DAO's governance be attacked, and how do DAOs defend themselves?
Because votes follow tokens, an attacker can try to borrow, rent or buy voting power, or slip a proposal through when few people vote.1,2 In April 2022, an attacker used a flash loan to pass a proposal at Beanstalk and take about $77 million in non-Bean assets; common defences include fixing voting power at a past snapshot and waiting out a timelock before execution.3,4,5,6
Why governance can be attacked
In a token-based DAO, voting power follows tokens.7 So anyone who can get enough tokens, for long enough, can try to steer a vote. Here are the main ways researchers and DAOs describe.1,2,4
- Buying votes. A group of researchers wrote in a 2023 paper that vote buying "has been a longstanding concern of DAO organizers". A briber can pay holders to vote a certain way, scaled to their token holdings.1
- Borrowing votes. Tokens can be borrowed. In a flash loan, the borrowed tokens are paid back within the same transaction, so the borrower holds them for only a moment.4
- Low turnout. When few people vote, fewer tokens are needed to win. Arbitrum's May 2025 quorum proposal said its new quorum should still be high enough "to deter governance attacks".2
The Beanstalk attack, April 2022
In April 2022, Beanstalk, a stablecoin protocol, was governed on-chain by its holders.3,8 Beanstalk Farms, its development team, said it was attacked on 17 April 2022. Someone used a flash loan to exploit the governance process and send funds to a wallet they controlled.3
Immunefi, a security firm, published an analysis in January 2023. It said the attacker submitted two proposals. One sent the protocol's funds to the attacker. The other sent $250,000 worth of BEAN to Ukraine's official crypto donation address.4
Beanstalk let holders carry out an emergency proposal after a 1-day delay, if it had at least two-thirds of the voting power.4 According to Immunefi, a day after submitting the proposals the attacker flash-borrowed more than $1 billion from Aave, Uniswap and SushiSwap. They turned it into Beanstalk voting power, passed the proposal and ran it, then repaid the loan, all in one transaction.4
| Figure | |
|---|---|
| Total drained, according to Immunefi | $181 million4 |
| Non-Bean assets stolen, according to Beanstalk | About $77 million3 |
| What happened to the rest | Beanstalk says its team burned the remaining Beans in the attacker's contract; Immunefi says "the rest was successfully burned"3,4 |
Immunefi drew one lesson: being able to vote on and execute a proposal in the same transaction leaves a DAO open to flash-loan attacks.4 Beanstalk Farms called it "an attack on Beanstalk's governance model, not its economic design".8 It removed on-chain governance. It said a multisig of nine community members and contributors would run the protocol, with proposals voted on through Snapshot, until a safer system was built.8
Suppose a made-up DAO has 100,000,000 votes in place, and a rule like Beanstalk's emergency route needs two-thirds of all voting power. Someone who adds B new votes holds B ÷ (100,000,000 + B). That reaches two-thirds when B is 200,000,000, twice the existing votes. In general, an outsider needs twice the existing voting power to hold two-thirds.4
Defences
| Defence | How it helps |
|---|---|
| Snapshots of voting power | OpenZeppelin's voting code keeps a history of votes, so a vote can use balances at a past block "to protect against flash loans and double voting"5 |
| A voting delay | Voting power is fixed some time after a proposal is published, before voting starts6 |
| A timelock | A passed proposal waits before it runs, so users can leave if they disagree6 |
| Late-quorum protection | An OpenZeppelin module keeps voting open for a minimum time after the quorum is reached, as "a security protection against large voters"5 |
| An emergency body | Arbitrum's constitution gives a 12-member Security Council, which signs from a multisig, powers to take certain emergency actions9 |
Snapshot explains why a fixed snapshot matters. Without one, a user could vote, move their tokens to another account and vote again.10 Its documentation also warns that tokens acquired after a proposal is created don't count toward that proposal.11
Defences can bring risks of their own. OpenZeppelin warns that letting accounts other than the Governor propose or cancel in its timelock is risky: they could act as the timelock, bypassing governance, and cancel approved proposals.6 Arbitrum's constitution lets the DAO change the Security Council's powers, or remove it entirely, through a constitutional proposal.9
- DAO Decentralization: Voting-Bloc Entropy, Bribery, and Dark DAOs (version 1). James Austgen, Andrés Fábrega, Sarah Allen, Kushal Babel, Mahimna Kelkar and Ari Juels, arXiv:2311.03530, 6 November 2023.
- [Constitutional] AIP: Constitutional Quorum Threshold Reduction. Arbitrum DAO governance forum, post by the forum account "Arbitrum", 2 May 2025.
- Beanstalk Governance Exploit. Beanstalk Farms, Beanstalk blog, 19 April 2022.
- Hack Analysis: Beanstalk Governance Attack, April 2022. Immunefi, a security firm (article by one of its smart contract triagers), 9 January 2023.
- Governance API reference. OpenZeppelin Contracts 5.x documentation (read 24 October 2026).
- How to set up on-chain governance. OpenZeppelin Contracts 5.x documentation (read 24 October 2026).
- Decentralized autonomous organizations (DAOs). ethereum.org (page last updated 26 June 2026; read 24 October 2026).
- Beanstalk: The Path Forward. Beanstalk Farms, Beanstalk blog (last updated 1 July 2022), 25 May 2022.
- The Amended Constitution of the ArbitrumDAO. Arbitrum DAO governance documentation (read 24 October 2026).
- FAQ. Snapshot documentation (read 24 October 2026).
- Create a proposal: snapshot block number. Snapshot documentation (read 24 October 2026).
General education built from the publicly available sources listed above. Not financial, legal, tax or investment advice. Naming a company, project or regulator is not an endorsement either way. Last checked 2026-10-24. Terms and disclaimer.