PDF Reader MCP is a Model Context Protocol server for reading PDF documents. In versions 2.2.0 and later prior to 3.0.1, when "MCP_TRANSPORT=http" enables the opt-in HTTP server, "@sylphx/pdf-reader-mcp" reads "MCP_API_KEY" and logs that "X-API-Key" authentication is enabled but never validates the "X-API-Key" header on incoming requests. The "/mcp" endpoint consequently accepts unauthenticated clients. With the default bind address of "0.0.0.0", any client able to reach the port can invoke every PDF tool and read any PDF the server process can open on the host, despite the misleading authentication-enabled startup log. URL-based sources additionally permit limited server-side request forgery; private and loopback destinations are blocked by default unless "--allow-private-ips" is set. The default "stdio" transport is unaffected. This issue is fixed in version 3.0.1.