Self-driving cars will prove an irresistible target for hackers if they ever hit the roads, a top security executive has warned.

Speaking exclusively to the Guardian, Eddie Schwartz, the vice president of global security solutions for Verizon's enterprise subsidiary, said that the cyber-security industry is still 40 years from maturity, and that the first half of the 21st century will see the number of targets increase exponentially.

"All of the major automobile manufacturers are working on self-driving cars," Schwartz explained. "For cars to be able to self-drive, they have to be able to negotiate with each other. You can't negotiate something like that without having some security principles behind it. So cars have to do basic things that we do with each other, like recognise each other – authentication.

"OK, I authenticate to you, that means there has to be an underlying artefact, a certificate or something like it that says 'you're an authorised car, and I'm an authorised car, therefore we can exchange this information really fast.' And you stop and I turn.

Schwartz described "a million applications" in the car industry alone designed for machine-to-machine communications with potentially a million underlying security issues.

Even normal cars are susceptible to hacking attacks. In August, a pair of researchers demonstrated attacks on a Ford SUV and Toyota Prius which enabled them to slam on the brakes, jerk the steering wheel, or accelerate the car using a laptop plugged into the the diagnostics port.

In 2011, a different team of researchers managed to penetrate similar systems through bluetooth, mobile data and even a malicious audio file burned onto a CD played in the car's media player.

But self-driving cars have many more avenues of communication with the outside world, and – definitionally – less oversight from a driver to correct any errors.

A ransom for your medical data?

As well as self-driving cars, Eddie Schwartz cautioned that the entire field of machine-to-machine communications, also known as "the internet of things", presents an enticing target to hackers.

"How many IP-based [internet connected] devices does the average person have in their home today? Most people can't even count them. If you ask them, they would probably say 'oh, I have two computers and a whatever', but the reality is it's probably more like 20 to 30 if they start thinking about it… You're going to see a spill from 4 or 5bn IP devices to hundreds of billions over the next 10 years."

Schwartz cautioned that with the growth of new devices and services in the health space the potential for malicious hacks will grow exponentially, including devices that gather intimate personal medical data.

"These are going to be embedded solutions. It's going to be wireless communications or NFC. These are machine-to-machine communications, and for critical care, they are going to have telemetry going on 24/7.

"There's an underlying security and privacy issue: imagine ransom-ware [software such as Cryptolocker that breaks devices and demands a fee to fix them] in that world."

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