{"id":"CVE-2026-40476","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-40476","generatedAt":"2026-10-28T03:24:51.568Z","title":"An attacker can send a query with thousands of repeated identical fields, causing excessive CPU usage during validation before execution begins.","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.","published":"2026-04-17T22:16:33.000Z","lastModified":"2026-10-26T21:10:00.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"4.0","score":6.9,"severity":"MEDIUM","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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-407"],"affected":["webonyx/graphql-php"],"epss":{"score":0.00637,"percentile":0.5025,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.64%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/webonyx/graphql-php/releases/tag/v15.31.5","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/webonyx/graphql-php/security/advisories/GHSA-68jq-c3rv-pcrr","tags":["Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"http://www.openwall.com/lists/oss-security/2026/09/14/26","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-40476","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}