API Security
API security addresses the unique vulnerabilities that arise when applications expose functionality through programmatic interfaces. As organizations shift to API-first architectures, microservices, and third-party integrations, APIs have become the primary attack surface for modern applications. The OWASP API Security Top 10 identifies critical risks including Broken Object Level Authorization (BOLA), mass assignment, excessive data exposure, and lack of rate limiting. APIs often inadvertently expose more data than their UI counterparts, accept parameters that bypass frontend validation, and may lack the authentication and authorization checks that browser-based interfaces enforce. REST, GraphQL, gRPC, and WebSocket APIs each present distinct security challenges. Effective API security requires authentication hardening, input validation, output filtering, rate limiting, proper error handling, and comprehensive logging across every endpoint.
| Date Added | Link | Excerpt |
|---|
Frequently Asked Questions
- What is the OWASP API Security Top 10?
- The OWASP API Security Top 10 is a list of the most critical API security risks, including Broken Object Level Authorization (BOLA), Broken Authentication, Broken Object Property Level Authorization, Unrestricted Resource Consumption, Broken Function Level Authorization, Server Side Request Forgery, Security Misconfiguration, and Lack of Protection from Automated Threats.
- Why are APIs harder to secure than web applications?
- APIs often expose more data and functionality than web UIs, accept complex input formats, lack the natural access controls of a browser interface, and are harder to monitor. They also tend to grow organically, creating shadow APIs that bypass security controls, and their machine-to-machine nature makes abuse detection more difficult.
- What tools are used for API security testing?
- Common tools include Burp Suite with API-focused extensions, Postman for manual testing, OWASP ZAP for automated scanning, Akto for API inventory and testing, and custom scripts for fuzzing API parameters. For GraphQL APIs, InQL and graphql-cop are essential. API specification files (OpenAPI/Swagger) are valuable for understanding and testing the full attack surface.