Process Compose: Browser DNS rebinding lets websites control local process-compose MCP tools
A malicious website can use DNS rebinding to control a developer's local process-compose MCP SSE listener when MCP SSE is enabled. The vulnerable path accepts browser-origin requests before any Host validation, Origin validation, or caller-secret check, then dispatches the requests into process-compose MCP tools. This advisory covers https://github.com/F1bonacc1/process-compose, confirmed at commit d56aa59df04b72f8644811ac581a051bec05e485. The issue is in the MCP SSE transport, not the Gin REST API. The REST API token middleware …