Dropbox Dash MCP Server DNS Rebinding via Missing Host Header Validation

The Dash MCP server bound its listener to the loopback address but never checked the host a request named. src/mcp_server_dash.py constructed the server for its network mode with the interface restricted to loopback and no transport-security settings, so a name that had been pointed at the loopback address still reached the listener while carrying the attacker's host name. A page in a visitor's browser could therefore drive the local server and invoke its company-search and file-detail tools under the Dropbox credential the server holds. Only the network mode was reachable this way; the standard input mode was not. The fix supplies transport-security settings that enable host checking and allow only the loopback name and port, rejecting other hosts before a tool runs. The repository publishes no versions, so the affected boundary is the commit preceding the fix.