Can someone write a computer virus that causes physical harm to the computer user?

I think some of the answers are not clear about the difference between computers and the equipment/systems they control. Certain examples mentioned also describe SCADA systems, where the actual damage was done by the industrial equipment connected to computers.

A computer is basically a data processing device that can take some input, store it, process it, and output it. Its ability to cause damage depends on what that output is piped to. As an example, a Raspberry Pi sitting in a case on a desktop somewhere will cause very little harm if its pins are not connected to anything. Yes, someone could make the desktop environment on the operating system project certain colors and patterns on its attached monitor that may cause certain reactions (epilepsy is one susceptible condition to this), but that is a long way from it controlling medical equipment, industrial machinery or utilities.

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Unfortunately, movies and television do not do the subject justice; they downplay some real dangers of computers because they are not interesting enough for film, while making up computer control capabilities that are exaggerated or just simply non-existent. One of my pet peeves is the “re-routing” attack; you cannot re-route something to infrastructure that does not exist or is not connected to the source infrastructure in the first place.


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A computer must have the physical capability to perform a certain action. My e-ink display Kindle sitting on my desk will not build itself into a killer robot, no matter who remotely exploits it with what virus.