The client-side field level encryption support in the MongoDB Python Driver can treat a key management endpoint value ending in .sock as a local Unix domain socket path rather than a remote host. A user with write access to the encryption key metadata stored in the database can cause an application using the driver to open connections to local sockets on the application host. Data sent over these connections is limited to the start of a TLS handshake, so no chosen content is transmitted.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.