What Is Smart Contract Audit?
A smart contract audit is a systematic security review performed by specialized firms (Trail of Bits, OpenZeppelin, Certik, etc.) to identify vulnerabilities, logic errors, and potential attack vectors in a protocol's smart contract code. Audits examine both the code itself and the economic logic to ensure the protocol behaves as intended under all conditions.
How Smart Contract Audit Works
Audits range in depth from automated scanning (finding common vulnerability patterns) to manual expert review (analyzing complex interactions and edge cases). Top-tier audits include formal verification — mathematically proving that certain properties hold under all inputs. Most serious DeFi protocols undergo multiple audits from different firms before launching.
Why It Matters for Traders
While an audit is necessary, it's not sufficient for safety. Many audited protocols have been exploited (often through attack vectors not covered by the audit scope). When evaluating a DeFi protocol: check how many audits were performed and by whom, whether the audit findings were addressed, whether the deployed code matches the audited version, and whether the protocol has a bug bounty program. Unaudited protocols carry extreme risk.