Unauthorized intrusion prevention device, unauthorized intrusion prevention method and unauthorized intrusion prevention program

摘要

An intrusion prevention device (10) receives, from a control target device (30), a notification indicating a state of the control target device (30). The intrusion prevention device (10) receives a control command transmitted from a control device (20) to the control target device (30). When receiving the control command, the intrusion prevention device (10) determines whether to permit or block passage of the control command in accordance with the received state of the control target device (30).