Terrorists already use them to trigger bombs, but tech-security experts are finding that phones can also shut off pacemakers, make cars crash, hijack houses, exhaust batteries in hospital equipment, and take over electrical systems. “If I’m a bad guy, I’ll wait till there’s a major snowstorm or heat wave,” says Stuart McClure, chief technical officer at McAfee. “Then kill the heat or A/C” so that “the elderly die very easily.”

All you need to undermine an implantable cardioverter-defibrillator (ICD), apparently, is a custom-built transmitter that makes a smartphone function like a wireless device used by doctors. Such a phone could signal an ICD to spit out 830 volts—a lethal zap. Equally vulnerable are the tire-pressure monitoring systems in cars, which could be wirelessly told to inform the car’s computer to lock the tires at 70 miles per hour. The list goes on: house “smart meters,” appliances, external defibrillators—all are at risk. And our technological society will only invent more. “Only when these embedded computers start to kill a few people—one death won’t do it—will we take it seriously,” says McClure. – Newser