CVE-2026-63421

highpriority · track · 0EPSS 0.007 · 52 %ileUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.67% (52nd) EPSS
CVSS 7.5 · high
Is it mine?
1 products
Check your exposure
Who says so?
1 sources
osv

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · security-advisories@github.comexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USCWE-20USCWE-480USCWE-480US
04

affected products (1)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • GHSA-cqmq-8755-7xvhKeystone vulnerable to `graphql.maxTake` bypass with negative `take`2026-08-21ghsa · osvUS

    # Summary The value of `graphql.maxTake` can be bypassed by providing a negative input. This can be used to exceed the developer's 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](https://haxset.com) Security Scanner and validated by their team.

06

sources

Which sources assert this record, and when.

osvNVDCVE.orgMITRE
published 2026-08-21modified 2026-08-26
07

references (4) nvd

External citations — patches, advisories, analysis.

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