APIs now represent over 70% of all internet traffic. As organizations decompose monolithic applications into distributed microservices running on Kubernetes and serverless backends, the API attack surface has outpaced traditional Web Application Firewalls (WAF).

1. Why Traditional WAFs Fail to Protect APIs

Traditional WAFs rely on signature-based pattern matching (regex) to catch well-known injection strings such as SQL injection (SQLi) and Cross-Site Scripting (XSS).

However, the most dangerous API vulnerabilities—such as Broken Object Level Authorization (BOLA / IDOR)—look like completely valid HTTP requests. When user A sends a legitimate request for GET /api/v1/invoices/9842, a WAF cannot determine whether user A has authorization to access invoice 9842 belonging to company B.

2. Key Tenets of Dedicated API Protection

  1. Automated Shadow API Discovery: Continuous network traffic analysis to map undocumented, deprecated, and staging endpoints exposed without authentication.
  2. Schema Conformance Validation: Strict runtime enforcement of OpenAPI / Swagger specifications, rejecting unexpected query parameters and oversized JSON payloads.
  3. Behavioral Anomaly Detection: Baseline legitimate user usage patterns to block credential stuffing, API scraping, and automated business logic abuse.