Browser Auth

Browser Auth

This skill allows the agent to request the user to perform a manual login on a website and then capture the session cookies/localStorage for further automated work.

🚨 Security & Risk Mitigation

We take security seriously. Below is how we address common concerns related to remote browser control:

1. Remote Code Execution (RCE) Protection

• Always Sandboxed: Chromium runs with the system sandbox ENABLED. There is no option to disable it in the code. This prevents a malicious website from escaping the browser and executing code on your host.
• Isolation Recommendation: We recommend running this skill within an isolated container (Docker) or a dedicated VM for an extra layer of protection.

2. Token Leakage (Referrer Protection)

• Referrer Policy: The server enforces Referrer-Policy: no-referrer. This ensures that even if you navigate to an untrusted site, your secret AUTH_TOKEN is NEVER sent in the HTTP Referer header.
• URL Cleansing: The interface automatically clears the token parameter from your browser's address bar immediately after the page loads.

3. Data Sensitivity

• Session Artifacts: The session.json file contains active login cookies. Treat it with the same level of security as a password.
• Mandatory Cleanup: Always delete the session file immediately after the agent finishes its task.
• No Persistence: This skill does not store credentials long-term or exfiltrate them to external servers.

4. Network Exposure

• Default Local Bind: By default, the server binds to 127.0.0.1.
• Secure Access: If you need remote access, do not bind to 0.0.0.0 directly. Instead, use a secure tunnel like Tailscale, Cloudflare Tunnel (cloudflared), or an SSH tunnel.

When to Use

• When a website requires manual interaction to solve Captcha or 2FA.
• When bot detection prevents automated login.
• When you want to authorize an agent without sharing your password.

Workflow

1. Request Auth: Start the tunnel using scripts/auth_server.js.
2. Provide Link: Share the link (including token) with the intended user over a secure channel.
3. Wait for Session: The user logs in and clicks DONE in the web UI.
4. Verify: Use scripts/verify_session.js to confirm the session is valid.
5. Cleanup: Delete the session file once the task is complete.

Tools

Start Auth Server

AUTH_HOST=127.0.0.1 AUTH_TOKEN=mysecret node scripts/auth_server.js <port> <session_file>

Verify Session

node scripts/verify_session.js <session_file> <target_url> <expected_text>

Runtime Requirements

Requires: express, socket.io, playwright-core, and a system chromium-browser.