Securing GraphQL APIs with static analysis

GraphQL changes the threat model

Nested queries and introspection make it easy for attackers to enumerate sensitive fields. The OWASP API Security Top 10 highlights GraphQL-specific risks like mass assignment and field-level authorization gaps. Static checks can spot missing auth directives and unbounded query depth in schemas before deployment.

Static analysis techniques

• Require auth directives on root queries and mutations; flag anonymous access.
• Set query depth and complexity limits; reject lists without pagination.
• Disable introspection in production; allow in staging only.
• Validate input types to avoid injection; avoid generic JSON scalars for IDs.
• Mark personally identifiable fields and ensure role-based guards exist.

The API security scanner compares schema rules against known GraphQL exploit patterns and suggests safer defaults.

Combine SAST with runtime controls

Enforce persisted queries, apply rate limits per token, and log resolver-level metrics. Feed anomalies back into the spec so future versions ship with tighter rules. When introducing breaking schema changes, pair them with deprecations and changelog entries.

Best practices

• Use SDL linting in CI alongside OpenAPI security scans for REST components.
• Document deprecations and removal timelines to avoid zombie fields.
• Provide example queries that respect least privilege and pagination.