CVE-2026-63421
Keystone: `graphql.maxTake` bypass with negative `take`
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Keystone: `graphql.maxTake` bypass with negative `take`
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.
- Record
CVE-2026-63421- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-20, CWE-480
- Updated
- 2026-11-02
EUVDEUVD-2026-64134
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.
- Record
EUVD-2026-64134- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-cqmq-8755-7xvh
Keystone vulnerable to `graphql.maxTake` bypass with negative `take`
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 Security Scanner and validated by their team.
- Record
GHSA-cqmq-8755-7xvh- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-20, CWE-480
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-63421- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-20, CWE-480
- Updated
- 2026-11-02
OSV
Keystone: `graphql.maxTake` bypass with negative `take`
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.
- Record
CVE-2026-63421- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-20, CWE-480
- Updated
- 2026-11-02
OSVGHSA-cqmq-8755-7xvh
Keystone vulnerable to `graphql.maxTake` bypass with negative `take`
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 Security Scanner and validated by their team.
- Record
GHSA-cqmq-8755-7xvh- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-20, CWE-480
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
@keystone-6/corenpm |
through 6.5.2 | 6.5.3 |
@keystone-6/corenpm |
before 6.5.3 | 6.5.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-63421 is a high vulnerability (CVSS 7.5) in Keystonejs Keystone, published August 21, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.67%, the 52nd percentile. Fixed in @keystone-6/core 6.5.3.
References
github.com/keystonejs/keystone/security/advisories/GHSA-cqmq-8755-7xvh
nvd.nist.gov/vuln/detail/CVE-2026-63421