Important Distinction

• scanner.py
  Performs non-intrusive version checking only (safe for audits and inventories).

• exploit.py
  Demonstrates how the workflow expression evaluation system can be abused in vulnerable versions.
  ⚠️ This file is an exploit, not just a PoC, and is intended only for local labs.

Local Lab Setup (Docker)

The vulnerable environment was created using the official n8n Docker image.

Start Vulnerable n8n Instance

• n8n UI will be available at:
  http://localhost:5678
• Version 1.121.0 is intentionally vulnerable for testing purposes.
• Since it is an authenticated RCE, you should create an account at http://localhost:5678/setup and provide your credentials in the exploit arguments when running the script

Demonstration Screenshot

The image below shows a Set node evaluating a workflow expression and returning command output inside the workflow execution result.
This behavior occurs due to unsafe expression evaluation in vulnerable versions.

Scanner Usage (Safe)

Example Output

Exploit Script

The exploit script:

• Authenticates to n8n
• Deploys a crafted workflow
• Triggers workflow execution
• Demonstrates abuse of the expression evaluation system
• Cleans up the workflow afterward

⚠️ This script must only be used on systems you own or have explicit permission to test. Example: