Definition ∞ An external call flaw refers to a security vulnerability in a smart contract that arises from its interaction with other external contracts or addresses. This type of flaw occurs when a contract does not properly validate or handle the return values or side effects of calls made to untrusted external code. Such a vulnerability can allow malicious actors to manipulate contract state, drain funds, or execute unintended operations. It represents a significant risk in decentralized applications.
Context ∞ News reports on smart contract exploits frequently detail external call flaws as the root cause of security breaches in decentralized finance protocols. These incidents highlight the complexity of secure smart contract development and the importance of thorough security audits. Understanding external call flaws helps the community assess the robustness of various blockchain projects.