Improper input validation in Keystonejs Keystone
CVE-2026-63421
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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Keystonejs Keystone — versions < 6.5.3
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-63421?
- CVE-2026-63421 is a high-severity vulnerability in Keystonejs Keystone, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2026-08-21.
- How severe is CVE-2026-63421?
- High severity. CVSS v3 base score is 7.5 out of 10.