{"id":"CVE-2026-75507","summary":"GraphQL-core: Denial of service via quadratic complexity in the OverlappingFieldsCanBeMerged validation rule","details":"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.","aliases":["GHSA-vj8h-fx38-h3vc"],"modified":"2026-10-23T02:45:18.745762180Z","published":"2026-10-22T16:12:38.424Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75507.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-400","CWE-407"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75507.json"},{"type":"FIX","url":"https://github.com/graphql-python/graphql-core/commit/150e59814d97d12140be005a558c93188ef89198"},{"type":"FIX","url":"https://github.com/graphql-python/graphql-core/commit/29c2753a7ee30a96a4109e7c6add1a2dae0497d7"},{"type":"WEB","url":"https://github.com/graphql-python/graphql-core/releases/tag/v3.2.12"},{"type":"WEB","url":"https://github.com/graphql-python/graphql-core/releases/tag/v3.3.0rc1"},{"type":"ADVISORY","url":"https://github.com/graphql-python/graphql-core/security/advisories/GHSA-vj8h-fx38-h3vc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-75507"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/graphql-python/graphql-core","events":[{"introduced":"b9b80c016edd1ea72be00d6dd2698be21a8cb875"},{"fixed":"af6addb1bf39e3b111ae7b805d774326a02f1079"},{"introduced":"27c900bcb1fb54f8a945f383ee61d4f95330ff06"},{"fixed":"2d72d39ce7107226b9bcd5cc47835a19da0c2c87"},{"fixed":"150e59814d97d12140be005a558c93188ef89198"},{"fixed":"29c2753a7ee30a96a4109e7c6add1a2dae0497d7"}],"database_specific":{"extracted_events":[{"strategy":"StringRangeExpression","range":[{"introduced":"3.0.0"},{"fixed":"3.2.12"}],"source":"AFFECTED_FIELD"},{"range":[{"introduced":"3.3.0a1"},{"fixed":"3.3.0rc1"}],"source":"AFFECTED_FIELD","strategy":"StringRangeExpression"},{"source":"REFERENCES_COMMIT","range":[{"fixed":"150e59814d97d12140be005a558c93188ef89198"}]},{"source":"REFERENCES_COMMIT","range":[{"fixed":"29c2753a7ee30a96a4109e7c6add1a2dae0497d7"}]},{"range":[{"fixed":"af6addb1bf39e3b111ae7b805d774326a02f1079"}],"source":"REFERENCES_TAG","original_tag":"v3.2.12"},{"source":"REFERENCES_TAG","original_tag":"v3.3.0rc1","range":[{"fixed":"2d72d39ce7107226b9bcd5cc47835a19da0c2c87"}]}]}}],"versions":["v3.2.11","v3.3.0rc0","v3.3.0b2","v3.3.0b1","v3.2.10","v3.2.9","v3.2.8","v3.2.7","v3.2.6","v3.2.5","v3.2.4","v3.2.3","v3.2.2","v3.2.1","v3.2.0","v3.2.0rc5","v3.2.0rc4","v3.2.0rc3","v3.2.0rc2","v3.2.0rc1","v3.1.5","v3.1.4","v3.1.3","v3.1.2","v3.1.1","v3.1.0","v3.1.0b2","v3.1.0b1","v3.1.0b0","v3.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-75507.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}