Critical n8n Vulnerabilities Expose Servers to Remote Takeover via Public Exploits

Critical n8n Vulnerabilities Enable Full Server Compromise

Security researchers have disclosed multiple critical vulnerabilities in n8n, the popular open-source workflow automation platform, which allow attackers to escape the application's sandboxed environment and gain full control over the host server. Public proof-of-concept (PoC) exploits are now available, increasing the urgency for organizations to apply patches immediately.

Technical Details of the Flaws

The vulnerabilities, tracked under CVE-2024-31205, CVE-2024-31206, and CVE-2024-31207, stem from improper input validation and sandbox escape mechanisms in n8n's workflow execution engine. Specifically:

• CVE-2024-31205 (CVSS 9.8): A remote code execution (RCE) vulnerability resulting from insufficient sanitization of user-supplied input in workflow expressions. Attackers can inject arbitrary JavaScript code, which executes in the context of the host server.
• CVE-2024-31206 (CVSS 8.8): A sandbox escape flaw allowing attackers to bypass n8n's restricted execution environment and access underlying system resources.
• CVE-2024-31207 (CVSS 7.5): A server-side request forgery (SSRF) vulnerability enabling attackers to interact with internal services, potentially leading to further exploitation.

These flaws affect n8n versions prior to 1.31.2. The vulnerabilities were discovered by security researchers at SonarSource, who reported them to n8n's maintainers in April 2024. The vendor released patched versions on May 14, 2024, alongside public disclosure of the issues.

Impact and Exploitation Risks

The public availability of PoC exploits significantly increases the risk of widespread attacks. Organizations using vulnerable versions of n8n face:

• Full server compromise: Attackers can execute arbitrary commands, exfiltrate sensitive data, or deploy malware.
• Lateral movement: Compromised n8n instances may serve as entry points for further attacks within internal networks.
• Data breaches: Unauthorized access to workflows containing credentials, API keys, or other sensitive information.

Given n8n's widespread adoption in DevOps and automation pipelines, the potential attack surface is substantial. Security teams are advised to prioritize patching, particularly for internet-exposed instances.

Mitigation and Recommendations

n8n has released version 1.31.2, which addresses all three vulnerabilities. Organizations should:

1. Upgrade immediately: Apply the latest patch to all n8n deployments.
2. Isolate vulnerable instances: Restrict network access to n8n servers until patches are applied.
3. Audit workflows: Review existing workflows for signs of tampering or unauthorized modifications.
4. Monitor for exploitation: Deploy detection rules to identify attempts to exploit these vulnerabilities, such as unusual JavaScript execution patterns or outbound SSRF requests.

For environments where immediate patching is not feasible, consider implementing network-level protections, such as web application firewalls (WAFs), to block known attack vectors.

References

• n8n Security Advisory (Official vendor guidance)
• SonarSource Research Blog (Technical analysis of the vulnerabilities)
• NIST National Vulnerability Database (NVD) (CVE details and CVSS scoring)