How to Secure Your APIs
Apply API Threat Detection.
Validate all data coming in via your APIs against a list of what are considered permissible inputs into the system—and make it as restrictive as possible. Better validation that incoming API requests are realistic user inputs at realistic rates helps prevent unwanted access to your APIs. And scan any inputs to spot patterns associated with common attacks such as SQL injection or script injection.
Turn on SSL for APIs.
Securing consumption of backend APIs through configuration of mutual SSL between an API gateway and the end user device secures your app from man in the middle (MITM) attacks. SSL ensures the integrity of all exchanges between the client app and backend server. This is a simple policy to implement, and there’s no downside to doing it. Simply put: Enforcing SSL minimizes the risk of MITM exposure.
Authenticate and Authorize API Access.
A strong authentication and authorization system must be in place for APIs. OAuth is often the most appropriate authorization technique as it standardizes multiple important access-related challenges for API publishers. But your OAuth solution must be designed to ensure that the process of OAuth-based authentication does not impact the performance of applications built against your API.