Access control misconfiguration occurs when security settings that manage user permissions are improperly set, allowing unauthorized individuals to access sensitive systems or data. This can result from default settings not being changed, incorrect permission assignments, or overly broad sharing options. Such misconfigurations are a common vulnerability in web applications, cloud environments, and internal networks, potentially leading to data breaches, loss of sensitive information, or system compromise. Regular audits, adherence to the principle of least privilege, and continuous monitoring are essential to prevent and detect access control misconfigurations.