GraphQL Under Siege: 5 Critical API Security Pitfalls

Overview

GraphQL is powerful, flexible, and increasingly popular — but it introduces security challenges that traditional REST APIs don't face. Here are the five most common issues we encounter during API security assessments.

1. Introspection Enabled in Production

GraphQL introspection lets anyone query the entire schema. In production, this hands attackers a complete map of your API surface.

2. Broken Object-Level Authorization (BOLA)

GraphQL resolvers often lack per-field authorization checks. We frequently find that users can query data belonging to other users by simply changing an ID argument.

3. Nested Query Denial of Service

Deeply nested queries can consume exponential server resources. Without query depth limiting, a single request can bring down the API.

4. Batch Query Attacks

GraphQL allows sending multiple operations in a single request. Attackers use this to bypass rate limiting on authentication endpoints — sending thousands of login attempts in one HTTP request.

5. Field-Level Information Disclosure

Error messages in GraphQL often reveal internal field names, types, and database structure — even when introspection is disabled.

Remediation Summary

• Disable introspection in production
• Implement query depth and complexity limits
• Add per-resolver authorization checks
• Rate-limit by operation count, not just HTTP requests
• Sanitize error messages