It was found that the argument --root-ca-file in the Controller Manager configuration file is not set as appropriate. This argument contains the path to the certificate file used for API server connection needed for relevant proccesses. Connection established without verifying the certificate could be subject to Man In the Middle attacks.
Recommended Mitigation
It is recommended to edit the Controller Manager configuration file on the master node and set the path to the certificate bundle file as a parameter to the --root-ca-file argument.