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.
https://github.com/tomerfiliba-org/rpyc/security/advisories/GHSA-h5cg-53g7-gqjw
https://gist.github.com/renbou/957f70d27470982994f12a1d70153d09