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.
Attack Parameters
Impact Assessment
CVSS Vector v3.1