GraphQL Security
GraphQL security encompasses the practices and controls needed to protect GraphQL APIs from unique attack vectors such as introspection abuse, deeply nested query attacks, excessive data exposure, and authorization bypass.
GraphQL is a query language for APIs that allows clients to request exactly the data they need. While this flexibility improves developer experience, it introduces security challenges that differ significantly from traditional REST APIs. Unlike REST, where each endpoint returns a fixed data structure, GraphQL exposes a single endpoint that accepts complex queries, making traditional security approaches insufficient.
Key security concerns include introspection queries that reveal the entire API schema to attackers, deeply nested or aliased queries that consume excessive server resources (denial-of-service via query complexity), batch queries that bypass rate limiting by combining many operations into a single request, and over-fetching through field-level authorization gaps where users can query fields they should not have access to.
Securing GraphQL APIs requires disabling introspection in production environments, implementing query depth and complexity limits, enforcing field-level authorization rather than relying solely on resolver-level checks, setting timeouts on query execution, and rate limiting based on query complexity rather than request count. Tools such as GraphQL Armor, graphql-depth-limit, and graphql-query-complexity help enforce these controls. Organizations should also implement persistent queries or query allowlists in production to prevent arbitrary query execution and conduct regular security audits of their GraphQL schema to identify exposed sensitive fields.