CVE-2026-40476CWE-407

CVE-2026-40476

High · published April 18, 2026

CVSS v3.1
7.5
EPSS
1%
Percentile
53.8
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00732 · 53.8th percentile
Weakness
CWE-407 · Inefficient Algorithmic Complexity
Published
2026-04-18T02:16Z
Affected products (1)
ProductVersionsFixed in
webonyx/graphql-php< 15.31.515.31.5
References (3)
https://github.com/webonyx/graphql-php/releases/tag/v15.31.5 · [email protected]https://github.com/webonyx/graphql-php/security/advisories/GHSA-68jq-c3rv-pcrr · [email protected]http://www.openwall.com/lists/oss-security/2026/09/14/26 · af854a3a-2127-422b-91ae-364da2661108
EPSS history
Timeline
  • 17 APR 21:42Z
    graphql-php: Denial of Service via quadratic complexity in OverlappingFieldsCanBeMerged validation
    cvelistv5