CVE-2026-39397 is a critical-severity (CVSS 9.4) CWE-862 vulnerability in @delmaredigital/payload-puck. A fix is available for @delmaredigital/payload-puck — see the affected versions and patch details below.
@delmaredigital/payload-puc is missing authorization on /api/puck/* CRUD endpoints allows unauthenticated access to Puck-registered collections
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-2026-39397.
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-2026-39397 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 377,636 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.
@delmaredigital/payload-pucknpmDescription
Impact
All /api/puck/* CRUD endpoint handlers registered by createPuckPlugin() called Payload's local API with the default overrideAccess: true, bypassing all collection-level access control. The access option passed to createPuckPlugin() and any access rules defined on Puck-registered collections were silently ignored on these endpoints.
An unauthenticated remote attacker could:
- List all documents (including drafts) in any Puck-registered collection
- Read any document by ID (including drafts)
- Create new documents with arbitrary field values
- Update any document (including bypassing field-level access rules)
- Delete any document
- Read version history and restore arbitrary versions
In typical installations, the affected scope is the collection backing the website's pages (default slug: pages). For most users this means an attacker could read, modify, create, or delete every page on the website — including unpublished drafts and version history.
Scope is limited to collections explicitly registered with createPuckPlugin() — the endpoints validate the collection slug against an allowlist, so attackers cannot pivot to other Payload collections such as users, media, or business data not exposed to the plugin. The auto-created puck-templates, puck-ai-prompts, and puck-ai-context collections are also outside the allowlist; they have their own dedicated endpoints with separate authentication.
Other endpoints in the plugin (AI, styles, prompts, context, and the Next.js API route factories in src/api/) were unaffected — they had their own authentication checks.
Patches
Fixed in 0.6.23. All endpoint handlers in src/endpoints/index.ts now pass overrideAccess: false and forward req to Payload's local API, so collection-level access rules are evaluated against the current user.
Workarounds
If you cannot upgrade immediately, place a reverse-proxy or middleware authentication check in front of /api/puck/* to require an authenticated session before requests reach the plugin's handlers.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @delmaredigital/payload-puck | all versions | 0.6.23npm install @delmaredigital/payload-puck@0.6.23 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @delmaredigital/payload-puck, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @delmaredigital/payload-puck to 0.6.23 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-39397 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-2026-39397 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-39397. 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-2026-39397 in your dependencies?
O3 Security finds CVE-2026-39397 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.