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`graphql.maxTake` bypass with negative `take`

High
emmatown published GHSA-cqmq-8755-7xvh Jul 1, 2026

Package

npm @keystone-6/core (npm)

Affected versions

<=6.5.2

Patched versions

6.5.3

Description

Summary

The value of graphql.maxTake can be bypassed by providing a negative input.
This can be used to exceed the developers intended graphql.maxTake value, allowing queries to return results in excess of the graphql.maxTake value set.

Impact

This affects any project relying on graphql.maxTake to bound the number of items returned per query.

Patches

This issue has been patched in @keystone-6/core version 6.5.3.

If you cannot patch, you can workaround this by restricting take input values in your GraphQL queries to the bounded value, or by blocking negative values.

Credit

This issue was found by Haxset's Security Scanner and validated by their team.

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVE ID

CVE-2026-63421

Weaknesses

Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Learn more on MITRE.

Use of Incorrect Operator

The product accidentally uses the wrong operator, which changes the logic in security-relevant ways. Learn more on MITRE.

Credits