CVE-2026-40476

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/webonyx/graphql-php/releases/tag/v15.31.5	Release Notes
https://github.com/webonyx/graphql-php/security/advisories/GHSA-68jq-c3rv-pcrr	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:webonyx:graphql-php:*:*:*:*:*:*:*:*

History

21 May 2026, 18:15

Type	Values Removed	Values Added
CPE		cpe:2.3:a:webonyx:graphql-php::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
First Time		Webonyx Webonyx graphql-php
References	~~() https://github.com/webonyx/graphql-php/releases/tag/v15.31.5 -~~	() https://github.com/webonyx/graphql-php/releases/tag/v15.31.5 - Release Notes
References	~~() https://github.com/webonyx/graphql-php/security/advisories/GHSA-68jq-c3rv-pcrr -~~	() https://github.com/webonyx/graphql-php/security/advisories/GHSA-68jq-c3rv-pcrr - Vendor Advisory

17 Apr 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-17 22:16

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40476

Mitre link : CVE-2026-40476

CVE.ORG link : CVE-2026-40476

JSON object : View

Products Affected

webonyx

graphql-php

CWE

CWE-407

Inefficient Algorithmic Complexity

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