MCP auth: The difference between a bridge and a backdoor

Model Context Protocol (MCP) has gained significant traction for its ability to seamlessly integrate AI agents with various tools and services, simplifying complex integrations and promoting interoperability. However, the rapid adoption of MCP has exposed security vulnerabilities, such as unauthenticated servers, supply chain attacks, and drive-by localhost attacks, which highlight the need for robust security measures. These vulnerabilities arise from the tendency to prioritize functionality over security, leading to exposed MCP servers that can be exploited by attackers to execute unauthorized actions. The text emphasizes the importance of implementing authentication, using scoped tokens, and ensuring that MCP servers are not inadvertently exposed to the public internet. It argues that securing MCP infrastructure is crucial for its safe scaling and suggests using services like WorkOS to manage authentication and access securely. As the ecosystem evolves, the shift from early adoption to securing the infrastructure becomes necessary to prevent potential security breaches and maintain the momentum that MCP has gained.