{"id":"CVE-2026-75507","state":"PUBLISHED","title":"GraphQL-core: Denial of service via quadratic complexity in the OverlappingFieldsCanBeMerged validation rule","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.","publishedAt":"2026-10-22T16:12:38.424Z","updatedAt":"2026-10-23T21:08:40.217Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["graphql-python graphql-core"],"affected":[{"vendor":"graphql-python","product":"graphql-core","versions":[{"version":">= 3.0.0, < 3.2.12","status":"affected"},{"version":">= 3.3.0a1, < 3.3.0rc1","status":"affected"}]}],"references":["https://github.com/graphql-python/graphql-core/security/advisories/GHSA-vj8h-fx38-h3vc","https://github.com/graphql-python/graphql-core/commit/150e59814d97d12140be005a558c93188ef89198","https://github.com/graphql-python/graphql-core/commit/29c2753a7ee30a96a4109e7c6add1a2dae0497d7","https://github.com/graphql-python/graphql-core/releases/tag/v3.2.12","https://github.com/graphql-python/graphql-core/releases/tag/v3.3.0rc1"],"weaknesses":["CWE-400","CWE-407"],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/75xxx/CVE-2026-75507.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-75507","state":"PUBLISHED","datePublished":"2026-10-22T16:12:38.424Z","dateUpdated":"2026-10-23T21:08:40.217Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-08-17T20:49:21.598Z"},"containers":{"cna":{"title":"GraphQL-core: Denial of service via quadratic complexity in the OverlappingFieldsCanBeMerged validation rule","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"graphql-python","product":"graphql-core","versions":[{"version":">= 3.0.0, < 3.2.12","status":"affected"},{"version":">= 3.3.0a1, < 3.3.0rc1","status":"affected"}]}],"references":[{"url":"https://github.com/graphql-python/graphql-core/security/advisories/GHSA-vj8h-fx38-h3vc","name":"https://github.com/graphql-python/graphql-core/security/advisories/GHSA-vj8h-fx38-h3vc","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/graphql-python/graphql-core/commit/150e59814d97d12140be005a558c93188ef89198","name":"https://github.com/graphql-python/graphql-core/commit/150e59814d97d12140be005a558c93188ef89198","tags":["x_refsource_MISC"]},{"url":"https://github.com/graphql-python/graphql-core/commit/29c2753a7ee30a96a4109e7c6add1a2dae0497d7","name":"https://github.com/graphql-python/graphql-core/commit/29c2753a7ee30a96a4109e7c6add1a2dae0497d7","tags":["x_refsource_MISC"]},{"url":"https://github.com/graphql-python/graphql-core/releases/tag/v3.2.12","name":"https://github.com/graphql-python/graphql-core/releases/tag/v3.2.12","tags":["x_refsource_MISC"]},{"url":"https://github.com/graphql-python/graphql-core/releases/tag/v3.3.0rc1","name":"https://github.com/graphql-python/graphql-core/releases/tag/v3.3.0rc1","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","lang":"en","description":"CWE-400: Uncontrolled Resource Consumption","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-407","lang":"en","description":"CWE-407: Inefficient Algorithmic Complexity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-22T16:12:38.424Z"},"source":{"advisory":"GHSA-vj8h-fx38-h3vc","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-23T17:32:54.760212Z","id":"CVE-2026-75507","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-23T21:08:40.217Z"}}]}}}