VulnerabilityModified

CVE-2026-40476

An attacker can send a query with thousands of repeated identical fields, causing excessive CPU usage during validation before execution begins.

MEDIUM 6.9EPSS 0.64%

Does this matter?

Lower severity and a low EPSS score (0.64%). Track it; it rarely justifies an emergency change on its own.

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 4.0: 6.9 MEDIUMCVSS: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
EPSS: 0.64% probability · 50th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-407
Affected: webonyx/graphql-php
Source: security-advisories@github.com

EPSS trend

EPSS 0.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.