CVE-2026-63421

Keystone: `graphql.maxTake` bypass with negative `take`

Published: Aug 21, 2026Updated: Sep 9, 2026 Sources: CVE List NVDCWE-20

7.5HIGH

Description

Keystone is a content management system for Node.js. Prior to 6.5.3, the findMany resolver in packages/core/src/lib/core/queries/resolvers.ts compares the signed take argument directly with graphql.maxTake, allowing a remote unauthenticated GraphQL client to provide a negative take value whose magnitude exceeds the configured bound. The bypass also applies to relationship queries and can return more records than the developer intended, potentially exhausting service resources. This issue is fixed in version 6.5.3.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-20 CWE-480

Affected Products

keystonejs

oss-projectaka keystone-5, keystonejs/keystone, keystone

keystoneMixed

Web & CMS Plugins / cms-core

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

https://github.com/keystonejs/keystone/commit/9fb88b246950ce4de754a43fe6416f20403577b1

github.com

https://github.com/keystonejs/keystone/pull/9859

github.com

https://github.com/keystonejs/keystone/releases/tag/@keystone-6/core@6.5.3

github.com

and 1 more references View all →

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