The API Security Problem: Vulnerability Analysis and Risk Benchmarking

The API Security Problem

APIs have become the dominant application interface, yet security testing practices have not kept pace. This research analyzes findings from API security assessments of 300+ organizations conducted in 2024, revealing systemic vulnerabilities that automated scanners consistently miss.

OWASP API Security Top 10 in Practice

Broken Object Level Authorization (BOLA/IDOR) remains the most prevalent API vulnerability, appearing in 71% of assessments. Unlike SQL injection, BOLA requires understanding application business logic — it cannot be detected by static analysis or generic scanners. Attackers exploit BOLA to access other users' data by manipulating object identifiers.

Authentication and Authorization Flaws

Broken authentication appeared in 58% of assessments, manifesting as JWT vulnerabilities (algorithm confusion, weak secret keys, improper validation), OAuth implementation errors, and API key mismanagement. Mass Assignment — allowing clients to modify object properties not intended to be user-controlled — appeared in 44% of assessments.

GraphQL-Specific Issues

GraphQL APIs introduced unique security challenges. Introspection enabled in production (exposing the entire schema) appeared in 67% of GraphQL implementations. Unrestricted query depth and complexity enabling denial-of-service appeared in 51%. Batching attacks bypassing rate limits appeared in 38%.

Recommendations

Organizations should implement: object-level authorization checks in every API function (not relying on route-level controls), API gateway rate limiting and quota enforcement, comprehensive API inventory and discovery, and dedicated API security testing separate from web application assessments.