API Security Best Practices
API security best practices for authentication, object authorization, input validation, webhooks, abuse controls, monitoring, and continuous testing.
Read guideWeb Security
API security guides
Authentication, authorization, validation, monitoring, and abuse controls for APIs.
What these guides cover
API security protects an interface throughout design, implementation, deployment, operation, and retirement. The strongest baseline does not depend on one gateway or scanner: it inventories every exposed API, authenticates callers, authorizes the exact object and function, validates all inputs and downstream destinations, limits costly operations, minimizes returned data, and records enforcement decisions. These controls must account for valid-looking abuse as well as malformed attacks. Checks close to application logic are essential when policy depends on tenant ownership, workflow state, resource sensitivity, or the business meaning of an operation. Failure behavior must be explicit so a security dependency outage does not silently grant access.
Risks
- Unknown, deprecated, or inconsistently protected APIs
- Broken object and function-level authorization
- Injection, SSRF, replay, and unsafe downstream calls
- Data exposure, resource exhaustion, and weak telemetry
Control priorities
- API inventory, ownership, and retirement policy
- Credential validation and deny-by-default authorization
- Schema, destination, signature, and replay validation
- Resource limits, monitoring, and negative security tests
Recommended reading order
Work through the API security guide from inventory and identity to authorization, validation, abuse controls, data exposure, monitoring, and continuous testing. Use its checklist as both a design review and a regression-test plan.