{"cve":"CVE-2026-40476","nvd":{"published":"2026-04-17T22:16:33.360","modified":"2026-10-26T21:10:00.170","status":"Modified","description":"graphql-go is a Go implementation of GraphQL. In versions 15.31.4 and below, the OverlappingFieldsCanBeMerged validation rule performs O(n²) pairwise comparisons of fields sharing the same response name. An attacker can send a query with thousands of repeated identical fields, causing excessive CPU usage during validation before execution begins. This is not mitigated by existing QueryDepth or QueryComplexity rules. This issue has been fixed in version 15.31.5.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","score":6.9},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-407"],"references":["https://github.com/webonyx/graphql-php/releases/tag/v15.31.5","https://github.com/webonyx/graphql-php/security/advisories/GHSA-68jq-c3rv-pcrr","http://www.openwall.com/lists/oss-security/2026/09/14/26"],"products":["webonyx:graphql-php"],"source":"nvd","synced_at":"2026-10-26T21:38:48.864438205+00:00"},"epss":{"cve":"CVE-2026-40476","score":0.00637,"percentile":0.5025,"date":"2026-10-26"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}