CVE-2023-40027
LOWCVE-2023-40027 is a low-severity (CVSS 3.7) CWE-862 vulnerability in @keystone-6/core. O3 Security confirms whether CVE-2023-40027 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Conditionally missing authorization in @keystone-6/core
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
@keystone-6/corenpmDescription
Keystone is an open source headless CMS for Node.js — built with GraphQL and React. When ui.isAccessAllowed is set as undefined, the adminMeta GraphQL query is publicly accessible (no session required). This is different to the behaviour of the default AdminUI middleware, which by default will only be publicly accessible (no session required) if a session strategy is not defined. This vulnerability does not affect developers using the @keystone-6/auth package, or any users that have written their own ui.isAccessAllowed (that is to say, isAccessAllowed is not undefined). This vulnerability does affect users who believed that their session strategy will, by default, enforce that adminMeta is inaccessible by the public in accordance with that strategy; akin to the behaviour of the AdminUI middleware. This vulnerability has been patched in @keystone-6/core version 5.5.1. Users are advised to upgrade. Users unable to upgrade may opt to write their own isAccessAllowed functionality to work-around this vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @keystone-6/core | all versions | 5.5.1 |
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. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update @keystone-6/core to 5.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-40027 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 pinpoints whether CVE-2023-40027 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2023-40027. 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-2023-40027 in your dependencies?
O3 detects CVE-2023-40027 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.