  Recent years have witnessed a boom of connected medical devices, which brings
security issues in the meantime. Medical imaging devices, an essential part of
medical cyber-physical systems, play a vital role in modern hospitals and are
often life-critical. However, security and privacy issues in these medical
cyber-physical systems are sometimes ignored.
  In this paper, we perform an empirical study on imaging devices to analyse
the security of medical cyber-physical systems. To be precise, we design a
threat model and propose prospective attack techniques for medical imaging
devices. To tackle potential cyber threats, we introduce protection mechanisms,
evaluate the effectiveness and efficiency of protection mechanisms as well as
its interplay with attack techniques. To scoring security, we design a
hierarchical system that provides actionable suggestions for imaging devices in
different scenarios. We investigate 15 devices from 9 manufacturers to
demonstrate empirical comprehension and real-world security issues.
