API security

GraphQL API penetration testing

GraphQL changes the shape of API risk. A single endpoint can expose a large graph of objects, relationships and resolver behaviour, so testing has to focus on authorisation and abuse paths as much as input handling.

GraphQL-specific test areas

Testing should examine schema exposure, introspection, field-level authorisation, resolver behaviour, query depth, batching, object ownership and excessive data exposure.

  • Broken object and field-level authorisation
  • Batching and query-depth abuse
  • Sensitive fields exposed through nested relationships
  • Resolver injection, SSRF and business-logic paths

Why normal API checks are not enough

REST-style endpoint checklists can miss GraphQL issues because the attack surface is the schema, resolver logic and object graph rather than a list of URLs.

How to prepare for testing

Provide schema access, test accounts for each role, sample queries, tenant examples and notes on sensitive object ownership rules.

FAQ

Common questions

Should introspection be disabled?

It depends on the environment and threat model. Introspection is not the only risk, but public introspection can make discovery easier for attackers.

Do GraphQL APIs need rate limits?

Yes. Query complexity, depth, batching and expensive resolver behaviour should be controlled.

Can GraphQL testing include the web or mobile client?

Yes. Client traffic often helps identify real workflows, roles and sensitive resolver paths.

Choose when your next test starts.

Standard within 10 business days. Rapid as soon as the next business day.

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