GHSA-jxx9-px88-pj69 is a high-severity (CVSS 8.1) CWE-284 vulnerability in n8n-mcp. O3 Security confirms whether GHSA-jxx9-px88-pj69 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
n8n-MCP: Multi-tenant MCP requests fall back to process-level n8n credentials when tenant headers are absent or incomplete
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 GHSA-jxx9-px88-pj69.
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
GHSA-jxx9-px88-pj69 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 0 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.
n8n-mcpnpmDescription
Summary
When ENABLE_MULTI_TENANT=true, the HTTP transport documents that the target n8n instance is selected per-request from x-n8n-url / x-n8n-key headers. Requests that omitted those headers — or supplied only one of them — silently fell back to the process-level N8N_API_URL / N8N_API_KEY credentials configured for the operator's own n8n instance. As a result, an authenticated MCP tenant could cause n8n management calls to execute against the operator's instance instead of its own.
This affects HTTP-mode deployments of n8n-mcp that are run as a shared multi-tenant service. Single-tenant deployments (ENABLE_MULTI_TENANT unset or false) are not affected.
Impact
An authenticated MCP tenant exploiting this path could read and write workflows, executions, data-table contents, and credential metadata on the operator's n8n instance. If the operator's n8n permits Code-node execution that reaches OS-level modules, the path could escalate to remote code execution inside the operator's n8n runtime. The process-level N8N_API_KEY is, in practice, a high-privilege key — Community Edition keys are unscoped by default, and even Enterprise scopes were configured for the operator's own needs and would carry over wholesale to a tenant who triggered the fallback.
Patches
Fixed in n8n-mcp 2.51.2. The fix:
- Rejects header-less multi-tenant requests at the HTTP edge with HTTP 400 / JSON-RPC
-32602before any handler runs. - Refuses to construct an env-credential n8n API client when
ENABLE_MULTI_TENANT=true. - Closes secondary leak paths in trigger handlers and in the responses of
n8n_health_check,n8n_diagnostic,n8n_deploy_template, andn8n_audit_instanceso the operator's URL and env-key indicator are not surfaced to tenants.
Single-tenant behavior is unchanged.
Upgrade
# NPM
npx n8n-mcp@latest
# Docker
docker pull ghcr.io/czlonkowski/n8n-mcp:latest
Workarounds
If an immediate upgrade is not possible, any one of the following reduces or eliminates exposure:
- Disable multi-tenant mode. Set
ENABLE_MULTI_TENANT=false(or unset it) and run a separate n8n-mcp instance per tenant with that tenant's ownN8N_API_URL/N8N_API_KEY. This removes the affected code path entirely. - Reject malformed requests at a proxy. Require both
x-n8n-urlandx-n8n-keyheaders on every request and return 400 if either is missing. Neutralizes the primary header-omission path but does not address the secondary response-shape disclosures, so this is a partial mitigation only. - Reduce the blast radius of the operator API key. If your n8n instance supports API key scoping (Enterprise, or a Community Edition build that exposes scopes), provision the operator's
N8N_API_KEYwith the minimum scopes required for the operator's own n8n-mcp functions. This does not close the boundary break but limits what a falling-back tenant can do.
Credit
Reported by @u-ktdi.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | n8n-mcp | all versions | 2.51.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n-mcp. 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 n8n-mcp to 2.51.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jxx9-px88-pj69 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 GHSA-jxx9-px88-pj69 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 GHSA-jxx9-px88-pj69. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-jxx9-px88-pj69 in your dependencies?
O3 detects GHSA-jxx9-px88-pj69 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.