Industrial Cybersecurity & OT Risk worked example

USB Control Risk Reduction with impact of removable-media compromise of 18 score: a worked example

Push impact of removable-media compromise up to 18 score and the picture changes. This example computes every intermediate figure at that operating point. Use it when reviewing removable media policies, approved transfer stations, scanning, and exception handling for OT environments.

The inputs for this scenario

  • Impact of removable-media compromise: 18 score (raised for this scenario; the documented default is 7)
  • Likelihood of removable-media exposure: 6 score (unchanged)
  • USB control gap (weakness of safeguards): 5 score (unchanged)

Working through the calculation

  • Applying the documented formula (USB control risk score = removable media impact score × removable media exposure score × USB control weakness score) to the inputs above produces each figure below.
  • At this operating point the engine returns 10.55 score for usb control risk score, the number this scenario is built around.
  • At this operating point the engine returns 18 score for removable media impact score.
  • At this operating point the engine returns 6 score for removable media exposure score.
  • At this operating point the engine returns 5 score for usb control weakness score.

How this compares with the baseline

  • Against the tool's baseline example, where impact of removable-media compromise sits at 7 score and the headline result is 6.15 score, this scenario comes in 71.54% above the baseline at 10.55 score.
  • It computes a composite removable-media risk score by multiplying impact, exposure likelihood, and the weakness of existing USB controls on a consistent scale. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • USB control risk score: 10.55 score (headline result)
  • Removable media impact score: 18 score
  • Removable media exposure score: 6 score
  • USB control weakness score: 5 score

Run it with your numbers

  • Every input above is editable in the live USB Control Risk Reduction calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.