CVE-2026-40476: graphql-php is affected by a Denial of Service via quadratic complexity in OverlappingFieldsCanBeMerged validation

high Affects webonyx/graphql-php. Feed 2026.10.29.1, updated 2026-10-28; published 2026-04-14; advisory modified 2026-09-10.

graphql-php is affected by a Denial of Service via quadratic complexity in OverlappingFieldsCanBeMerged validation

Package: webonyx/graphql-php Composer
Affected versions: <15.31.5
Fixed in: 15.31.5
Severity: high CVSS 7.5
Exploitation: not on CISA KEV · EPSS 1% (50.4th percentile)
Published: 2026-04-14
Source: osv.dev

References

CWE-407

NVD record webonyx/graphql-php advisories

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Related advisories

CVE-2026-107376 high webonyx/graphql-php has unbounded recursion in parser that causes stack overflow on crafte same package: webonyx/graphql-php
GHSA-fc86-6rv6-2jpm high webonyx/graphql-php has quadratic validation cost in OverlappingFieldsCanBeMerged via inli same package: webonyx/graphql-php
CVE-2026-71488 high league/commonmark: Quadratic-time denial of service when parsing crafted Markdown same weakness: CWE-407
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