Sample reports

Sample report: The DAO

The DAO was a crowdfunded investment contract on Ethereum. In June 2016 an attacker used a reentrancy bug in its split function to drain about 3.6 million ETH, and the community answered with the hard fork that split Ethereum and Ethereum Classic. Below is the unedited automatic report scau.pro produced for the contract's verified source code.

Network

Ethereum

Language

Solidity

Contract

0xBB9bc244D798123fDe783fCc1C72d3Bb8C189413 (Etherscan)

Automatic first pass, shown without edits. The findings are generated by AI and are not verified by an auditor: some may be false positives, and some issues may be missed.

12 findings

• Critical: 1
• High: 3
• Medium: 6
• Low: 1
• Info: 1

1. Critical SWC-107 Reentrancy Contract.sol, line 556

   Reentrancy in DAO.splitDAO(): external call to newDAO.createTokenProxy.value(fundsToBeMoved)(msg.sender) occurs before the caller's balance/totalSupply are zeroed, allowing recursive split calls to move funds multiple times. This is the classic DAO vulnerability pattern.

2. High SWC-107 Reentrancy Contract.sol, line 195

   Reentrancy in TokenCreation.refund(): msg.sender.call.value(weiGiven[msg.sender])() is performed before totalSupply, balances and weiGiven are updated, allowing repeated refunds during fallback reentry.

3. High SWC-107 Reentrancy Contract.sol, line 480

   executeProposal() performs arbitrary external call p.recipient.call.value(p.amount)(_transactionData). Although proposal is closed afterwards, this enables arbitrary code execution/reentrancy into DAO functions during execution and should be guarded.

4. High SWC-105 Unprotected Ether Withdrawal Contract.sol, line 594

   DAO.newContract() can transfer the entire DAO balance to an allowed recipient if invoked via a passed proposal to address(this). This intentional upgrade path is highly privileged and can drain all funds if governance/allowed-recipient control is compromised.

5. Medium SWC-107 Reentrancy Contract.sol, line 99

   Reentrancy risk in ManagedAccount.payOut(): uses _recipient.call.value(_amount)() before returning. Callers relying on post-call accounting may be exposed; prefer checks-effects-interactions or withdrawal pattern.

6. Medium SWC-101 Integer Overflow and Underflow Contract.sol, line 212

   Potential arithmetic underflow in divisor(): closingTime - 2 weeks / closingTime - 4 days can underflow when closingTime is less than those durations, producing incorrect pricing logic in Solidity <0.8.

7. Medium SWC-101 Integer Overflow and Underflow Contract.sol, line 175

   Multiple arithmetic operations use unchecked uint math in Solidity <0.8, e.g. token = (msg.value * 20) / divisor(), balance additions, totalSupply additions, minQuorum calculations. Overflows/underflows can corrupt token balances and voting math.

8. Medium SWC-114 Transaction Order Dependence Contract.sol, line 58

   ERC20 approve race condition: approve() directly changes allowance from a non-zero value to another non-zero value, allowing a spender to front-run and spend both old and new allowance.

9. Medium SWC-104 Unchecked Call Return Value Contract.sol, line 176

   Unchecked low-level call in TokenCreation.createTokenProxy(): extraBalance.call.value(msg.value - token)() return value is ignored, so ETH forwarding failure is not handled and accounting can diverge.

10. Medium SWC-113 DoS with Failed Call Contract.sol, line 473

    DoS risk from push payments: executeProposal() throws if p.creator.send(p.proposalDeposit) fails, so a proposal creator contract with reverting fallback can prevent successful proposal execution.

11. Low SWC-104 Unchecked Call Return Value Contract.sol, line 453

    Unchecked return value of send() when refunding proposal deposit if recipient is no longer allowed: p.creator.send(p.proposalDeposit) return value is ignored and proposal deposit can become stuck/lost in accounting.

12. Info SWC-703 Contract.sol, line 1

    Use of deprecated Solidity 0.4-era constructs: throw, constant, sha3, unnamed fallback functions, and low-level call.value. These reduce maintainability and lack modern safety features such as automatic overflow checks.