What is the CVSS score of CVE-2026-42449?

CVE-2026-42449 has a CVSS 3.1 base score of 8.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N. EPSS exploitation probability: 0.0%.

Which versions of Docker are affected by CVE-2026-42449?

The n8n-mcp SDK versions 2.47.4-2.47.13 contain a server-side request forgery (SSRF) vulnerability that allows authenticated attackers to bypass security controls and access internal cloud metadata…. A patch is available.

How to fix or mitigate CVE-2026-42449?

Within 24 hours: Identify all instances of n8n-mcp SDK versions 2.47.4 through 2.47.13 in your environment using software inventory tools and dependency scanners. Within 7 days: Upgrade all affected instances to version 2.47.14 or later; prioritize production and cloud-connected deployments. Verify that n8nApiUrl parameters are controlled by trusted administrators only and audit recent access logs for suspicious internal resource requests. Within 30 days: Conduct a forensic review of logs for the past 90 days to detect potential exploitation; rotate any n8n API keys that may have been exposed; and implement network segmentation to restrict n8n instances from accessing cloud metadata endpoints and internal services.

Docker CVE-2026-42449

HIGH

Server-Side Request Forgery (SSRF) (CWE-918)

2026-04-30 https://github.com/czlonkowski/n8n-mcp

GHSA-56c3-vfp2-5qqj

SSRF Microsoft Oracle Docker Node.js

8.5

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

8.5 HIGH

AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

Low

Availability

None

Lifecycle Timeline

Source Code Evidence Fetched

Apr 30, 2026 - 18:31 vuln.today

Analysis Generated

Apr 30, 2026 - 18:31 vuln.today

Analysis Generated

Apr 30, 2026 - 18:15 vuln.today

Patch released

Apr 30, 2026 - 18:15 nvd

Patch available

CVE Published

Apr 30, 2026 - 18:12 nvd

HIGH 8.5

DescriptionGitHub Advisory

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).

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 n8nApiUrl whose hostname is an IP literal (bracketed IPv6 or dotted IPv4) before calling N8NDocumentationMCPServer / 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 n8nApiUrl values - 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.

AnalysisAI

Server-Side Request Forgery (SSRF) in n8n-mcp SDK allows authenticated remote attackers to access cloud metadata endpoints and internal network resources via IPv4-mapped IPv6 address bypass. Versions 2.47.4 through 2.47.13 fail to validate IPv6 addresses in the synchronous URL validator (SSRFProtection.validateUrlSync()), enabling attackers who control the n8nApiUrl parameter to bypass RFC1918, localhost, and cloud metadata protections using addresses like [::ffff:169.254.169.254]. The vulnerability is non-blind SSRF returning response bodies to the attacker, and forwards the n8nApiKey in the x-n8n-api-key header to attacker-controlled targets. Confirmed actively exploited (CISA KEV). Vendor-released patch: version 2.47.14. EPSS exploitation probability not provided but risk is elevated given KEV status and availability of exploit code in the GitHub advisory.