Security requirements for Apex classes and Flow security models differ in their approach:
- **Apex Classes**: Require explicit enforcement of CRUD (Create, Read, Update, Delete) and FLS (Field-Level Security) checks. Developers must programmatically implement these checks, especially when running in system mode, to prevent unauthorized data access or updates.
- **Flows**: Rely on the platform's built-in sharing settings and permissions. Flows typically operate in user mode, respecting the user's permissions and sharing rules by default. However, when configured to run in system mode, extra care is needed to ensure sensitive data is not exposed or modified without proper authorization.
Both models focus on validating data access and adhering to security best practices, but Apex classes demand more manual intervention to enforce these controls.