Vulnerability 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 Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Webonyx | Graphql-Php | < 15.31.5 |
Related Weaknesses (CWE)
References
- https://github.com/webonyx/graphql-php/releases/tag/v15.31.5Release Notes
- https://github.com/webonyx/graphql-php/security/advisories/GHSA-68jq-c3rv-pcrrVendor Advisory
FAQ
What is CVE-2026-40476?
CVE-2026-40476 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 na...
How severe is CVE-2026-40476?
CVE-2026-40476 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-2026-40476?
Check the references section above for vendor advisories and patch information. Affected products include: Webonyx Graphql-Php.