GHSA-8g7g-hmwm-6rv2 is a high-severity (CVSS 8.3) vulnerability in n8n-mcp. A fix is available for n8n-mcp — see the affected versions and patch details below.
n8n-mcp affected by path traversal, redirect-following SSRF, and telemetry payload exposure
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
Impact
n8n-mcp versions before 2.50.1 contained three independently-reported issues affecting deployments that run the n8n API integration:
-
Caller-supplied identifiers were not validated before being used as URL path segments by the n8n API client. An authenticated MCP caller passing a crafted workflow id could cause outbound requests carrying the configured n8n API key to land on other same-origin endpoints, bypassing handler-level access controls (including
DISABLED_TOOLS). -
Validated webhook, form, and chat trigger URLs followed redirects. A URL that passed initial validation could redirect the outbound request to a host that would otherwise have been rejected, with the response body returned to the caller. Reachable as non-blind SSRF over authenticated MCP calls.
-
Mutation telemetry stored unredacted operation payloads. On instances running with the default opt-in telemetry, partial-update operation diffs were uploaded without redaction. Operation values can carry the same node-parameter values the workflow contains, including bearer tokens, API keys, and webhook secrets.
Severity
CVSS 8.3 (HIGH). Exploitation requires an authenticated MCP caller and an n8n API integration configured with an n8n API key.
Patched versions
Upgrade to n8n-mcp >= 2.50.1.
Workarounds
- For issues (1) and (2): restrict network access to the HTTP transport (firewall, reverse-proxy ACL, or VPN) so only trusted callers can reach the MCP HTTP port; or switch to stdio mode, which exposes no HTTP surface for these issues.
- For issue (3): set
N8N_MCP_TELEMETRY_DISABLED=truein the environment before starting the server, or runnpx n8n-mcp telemetry disableonce.
Credit
Reported by @cybercraftsolutionsllc.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | n8n-mcp | all versions | 2.50.1npm install n8n-mcp@2.50.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n-mcp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update n8n-mcp to 2.50.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8g7g-hmwm-6rv2 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 GHSA-8g7g-hmwm-6rv2 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-8g7g-hmwm-6rv2. 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-8g7g-hmwm-6rv2 in your dependencies?
O3 Security finds GHSA-8g7g-hmwm-6rv2 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.