Summary
Affected
Deployments embedding n8n-mcp as an SDK using N8NDocumentationMCPServer or N8NMCPEngine with user-supplied InstanceContext on versions v2.47.4 through v2.47.13.
Patched
v2.47.14 and later.
- npm:
npx n8n-mcp@latest(or pin to>= 2.47.14) - Docker:
docker pull ghcr.io/czlonkowski/n8n-mcp:latest
Workarounds
If developers cannot upgrade immediately:
- Validate URLs before passing to the SDK, reject any
n8nApiUrlwhose hostname is an IP literal (bracketed IPv6 or dotted IPv4) before callingN8NDocumentationMCPServer/getN8nApiClient(). Accept only URLs with DNS-resolvable hostnames. - Restrict egress at the network layer, block outbound traffic from the n8n-mcp process to RFC1918 ranges (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16), link-local
169.254.0.0/16, and cloud metadata endpoints. Defense-in-depth against this class of issue and recommended even after upgrading. - Do not accept user-controlled
n8nApiUrlvalues, if the project's integration derives the URL from internal configuration only, this vulnerability is not reachable.
Upgrading to v2.47.14 is still strongly recommended.
Credit
Reported by @manthanghasadiya.
Impact
In the SDK embedder path (N8NDocumentationMCPServer constructor, getN8nApiClient(), and validateInstanceContext()), the synchronous URL validator in SSRFProtection.validateUrlSync() had no IPv6 checks. IPv4-mapped IPv6 addresses such as http://[::ffff:169.254.169.254] bypassed the cloud-metadata, localhost, and private-IP range checks. An attacker able to supply an n8nApiUrl value could cause the server to issue HTTP requests to cloud metadata endpoints (AWS IMDS, GCP, Azure, Alibaba, Oracle), RFC1918 private networks, or localhost services. Response bodies are returned to the caller (non-blind SSRF), and the n8nApiKey is forwarded in the x-n8n-api-key header to the attacker-controlled target.
The first-party HTTP server deployment was not primarily affected, it has a second async validator (validateWebhookUrl) that catches IPv6 addresses.
Impact category: CWE-918 (Server-Side Request Forgery).
Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside. Typical impact: access to internal metadata services, internal APIs, or cloud credentials.
CVE-2026-42449 has a CVSS score of 8.5 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.47.14); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2026-42449? CVE-2026-42449 is a high-severity server-side request forgery (SSRF) vulnerability in n8n-mcp (npm), affecting versions >= 2.47.4, < 2.47.14. It is fixed in 2.47.14. Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside.
- How severe is CVE-2026-42449? CVE-2026-42449 has a CVSS score of 8.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of n8n-mcp are affected by CVE-2026-42449? n8n-mcp (npm) versions >= 2.47.4, < 2.47.14 is affected.
- Is there a fix for CVE-2026-42449? Yes. CVE-2026-42449 is fixed in 2.47.14. Upgrade to this version or later.
- Is CVE-2026-42449 exploitable, and should I be worried? Whether CVE-2026-42449 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-42449 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-42449? Upgrade
n8n-mcpto 2.47.14 or later.