mcp-remote

Least-privilege permissions

• Run the proxy with minimal system access. Only grant file read/write permissions to directories it absolutely needs; do not run as administrator or root user.
• Restrict OAuth token storage. Keep credential files on an encrypted, separate drive if possible; use file-level encryption (like BitLocker or FileVault) rather than relying on folder passwords.
• Limit who can access proxy logs. Only authorized security and operations staff should read logs; use role-based access controls to prevent casual viewing of credentials or data.
• Rotate OAuth tokens regularly (monthly minimum). Treat tokens like passwords—retire old ones even if they seem safe.

Network isolation

• Require TLS encryption for all remote connections. Verify the remote server's security certificate is valid; reject self-signed certificates in production unless explicitly trusted and documented.
• Use a dedicated network segment or firewall rules. Do not allow the proxy to communicate with untrusted internal systems; isolate it from sensitive databases or internal tools.
• Disable direct internet access where possible. Route connections through a corporate VPN or proxy gateway so your organization can monitor and filter traffic.
• Block unnecessary ports and services. Disable any features on the proxy that are not actively used.

Monitoring

• Enable detailed audit logging for all OAuth token operations (issuance, refresh, revocation) and all remote connections—log which servers are contacted and when.
• Set alerts for suspicious patterns: unusual connection times, failed authentication attempts, or requests to unknown remote servers.
• Review logs weekly for unauthorized access, data volume spikes, or changes in proxy configuration.
• Monitor the GitHub repository for security advisories, updates, and vulnerability reports; subscribe to notifications and patch immediately.

Red flags to watch for

• Proxy process crashes or restarts frequently. This may indicate memory corruption or an attempted exploit.
• Unexplained network traffic to or from the proxy outside normal operation hours or to unfamiliar IP addresses.
• Authentication failures increasing suddenly or tokens expiring prematurely—possible signs of token compromise or man-in-the-middle attack.
• Remote MCP servers you did not authorize. Review the list of allowed servers regularly; if unknown servers appear, revoke access and investigate immediately.