CVE-2026-33326 — @keystone-6/core
MEDIUMCVE-2026-33326 is a medium-severity (CVSS 4.3) CWE-863 vulnerability in @keystone-6/core. A fix is available for @keystone-6/core — see the affected versions and patch details below.
@keystone-6/core: `isFilterable` bypass via `cursor` parameter in findMany
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-33326.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-33326 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@keystone-6/corenpmDescription
Summary
{field}.isFilterable access control can be bypassed in findMany queries by passing a cursor. This can be used to confirm the existence of records by protected field values.
The fix for CVE-2025-46720 (field-level isFilterable bypass for update and delete mutations) added checks to the where parameter in update and delete mutations however the cursor parameter in findMany was not patched and accepts the same UniqueWhere input type.
Impact
This affects any project relying on isFilterable behaviour (at the list or field level) to prevent external users from using the filtering of fields as a discovery mechanism. isFilterable access control using a function can be bypassed by using the cursor input.
This has no impact on projects using isFilterable: false or defaultIsFilterable: false for sensitive fields, or if you have otherwise omitted filtering by these fields from your GraphQL schema. (See workarounds)
Patches
This issue has been patched in @keystone-6/core version 6.5.2.
Workarounds
To mitigate this issue in older versions where patching is not a viable pathway.
- Set
{field}.isFilterable: falsestatically for relevant fields to prevent filtering by them earlier in the access control pipeline (that is, don't use functions) - Set
{field}.graphql.omit.read: truefor relevant fields, which implicitly removes filtering by these fields your GraphQL schema
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @keystone-6/core | all versions | 6.5.2npm install @keystone-6/core@6.5.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @keystone-6/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @keystone-6/core to 6.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33326 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-33326 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-33326. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-33326 in your dependencies?
O3 Security finds CVE-2026-33326 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.