python-rpyc: Remote attacker can craft a class, resulting in remote code execution

In RPyC before 6.0.0, when a server exposes a method that calls the attribute named __array__ for a client-provided netref (e.g., np.array(client_netref)), a remote attacker can craft a class that results in remote code execution.

In RPyC 4.1.x through 4.1.1, a remote attacker can dynamically modify object attributes to construct a remote procedure call that executes code for an RPyC service with default configuration settings.