Vulnerability Description
GraphQL-core is a Python port of the GraphQL.js reference implementation. From 3.0.0 until 3.2.12 and 3.3.0rc1, the OverlappingFieldsCanBeMerged rule in specified_rules repeatedly compares fields that share response names and recursively re-compares flattened inline fragments during the validation phase. The prior named-fragment memoization does not cover this path, so nested repeated inline fragments can drive quadratic and worst-case O(n²·m²) CPU work before any resolver or AST-based depth or complexity control runs. An unauthenticated remote attacker can submit a shallow, highly compressible GraphQL query that pins a worker process and can saturate a multi-worker service. This issue is fixed in versions 3.2.12 and 3.3.0rc1.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/graphql-python/graphql-core/commit/150e59814d97d12140be005a55
- https://github.com/graphql-python/graphql-core/commit/29c2753a7ee30a96a4109e7c6a
- https://github.com/graphql-python/graphql-core/releases/tag/v3.2.12
- https://github.com/graphql-python/graphql-core/releases/tag/v3.3.0rc1
- https://github.com/graphql-python/graphql-core/security/advisories/GHSA-vj8h-fx3
FAQ
What is CVE-2026-75507?
CVE-2026-75507 is a vulnerability with a CVSS score of 7.5 (HIGH). GraphQL-core is a Python port of the GraphQL.js reference implementation. From 3.0.0 until 3.2.12 and 3.3.0rc1, the OverlappingFieldsCanBeMerged rule in specified_rules repeatedly compares fields that...
How severe is CVE-2026-75507?
CVE-2026-75507 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-75507?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.