A **DeFi hack** refers to a security breach or exploit targeting a decentralized finance (DeFi) platform, protocol, or smart contract. In such incidents, attackers exploit vulnerabilities in the code, design flaws, or poor security practices to steal funds, manipulate transactions, or otherwise compromise the system. DeFi hacks often result in significant financial losses because assets are held in smart contracts on the blockchain, and once stolen, they are difficult to recover.