As applications become more interconnected, securing the APIs that connect them is critical. An insecure API can expose sensitive data and lead to a full system compromise.
1. Broken Object Level Authorization (BOLA)
This occurs when an API endpoint exposes objects without proper access control checks. For example, an attacker changing /api/users/123 to /api/users/124 to access another user's data. Mitigation involves implementing object-level authorization checks on every request.
2. Broken Authentication
Weak authentication mechanisms can be easily compromised. Always use strong, standardized authentication protocols like OAuth 2.0 or OIDC. Implement rate limiting and lockout policies to prevent brute-force attacks.
3. Excessive Data Exposure
APIs should only return the data that is necessary for the client. Avoid serializing entire database objects to the client, as this can expose sensitive internal fields. Tailor each API response to the specific needs of the consumer.