On Practical Machinst, there's a fascinating thread about the manufacturer's lockdown on a high-priced, high-end Mori Seiki NV5000 A/40 CNC mill. The person who started the thread owns the machine outright, but has discovered that if he moves it at all, a GPS and gyro sensor package in the machine automatically shuts it down and will not allow it to restart until they receive a manufacturer's unlock code.
Effectively, this means that machinists' shops can't rearrange their very expensive, very large tools to improve their workflow from job to job without getting permission from the manufacturer (which can take a month!), even if their own the gear.
According to posts in the thread, many manufacturers have introduced this lockdown feature because their goods have found their way into Iran, violating the embargo. So now these machines can't be moved at all without the manufacturer's knowledge and consent, a situation that the manufacturers have turned into a business-opportunity by using the technology to assist in repossessing machines from delinquent lease-payers -- and requiring permission for privilege of deciding where to place their key capital assets.
I'm interested in the security implications of this. Malware like Stuxnet attacked embedded systems on computerized machines, causing them to malfunction in subtle ways. A subtly weakened or defective part from a big mill like the NV5000 might find its way into a vehicle or a high-speed machine, with disastrous consequences.
And since the mills are designed to be opaque to their owners, and to actively prevent their owners from reverse-engineering them (lest they disable the gyro/GPS), an infection would be nearly impossible to detect. Criminals and saboteurs are a lot less worried about voiding the warranty on your $100K business-asset than you are, and that asymmetry, combined with the mandate for opacity in the operations, presents a serious risk to machine shops and their customers (and their customers' users -- that is, everyone).
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