July 21, 2015
I was driving 70 mph on the edge of downtown St. Louis when the exploit began to take hold.
Though I hadn’t touched the dashboard, the vents in the Jeep Cherokee started blasting cold air at the maximum setting, chilling the sweat on my back through the in-seat climate control system. Next the radio switched to the local hip hop station and began blaring Skee-lo at full volume. I spun the control knob left and hit the power button, to no avail. Then the windshield wipers turned on, and wiper fluid blurred the glass.
As I tried to cope with all this, a picture of the two hackers performing these stunts appeared on the car’s digital display: Charlie Miller and Chris Valasek, wearing their trademark track suits. A nice touch, I thought.
The Jeep’s strange behavior wasn’t entirely unexpected. I’d come to St. Louis to be Miller and Valasek’s digital crash-test dummy, a willing subject on whom they could test the car-hacking research they’d been doing over the past year. The result of their work was a hacking technique—what the security industry calls a zero-day exploit—that can target Jeep Cherokees and give the attacker wireless control, via the Internet, to any of thousands of vehicles. Their code is an automaker’s nightmare: software that lets hackers send commands through the Jeep’s entertainment system to its dashboard functions, steering, brakes, and transmission, all from a laptop that may be across the country.
To better simulate the experience of driving a vehicle while it’s being hijacked by an invisible, virtual force, Miller and Valasek refused to tell me ahead of time what kinds of attacks they planned to launch from Miller’s laptop in his house 10 miles west. Instead, they merely assured me that they wouldn’t do anything life-threatening. Then they told me to drive the Jeep onto the highway. “Remember, Andy,” Miller had said through my iPhone’s speaker just before I pulled onto the Interstate 64 on-ramp, “no matter what happens, don’t panic.”1
As the two hackers remotely toyed with the air-conditioning, radio, and windshield wipers, I mentally congratulated myself on my courage under pressure. That’s when they cut the transmission.
Immediately my accelerator stopped working. As I frantically pressed the pedal and watched the RPMs climb, the Jeep lost half its speed, then slowed to a crawl. This occurred just as I reached a long overpass, with no shoulder to offer an escape. The experiment had ceased to be fun.
At that point, the interstate began to slope upward, so the Jeep lost more momentum and barely crept forward. Cars lined up behind my bumper before passing me, honking. I could see an 18-wheeler approaching in my rearview mirror. I hoped its driver saw me, too, and could tell I was paralyzed on the highway.
“You’re doomed!” Valasek shouted, but I couldn’t make out his heckling over the blast of the radio, now pumping Kanye West. The semi loomed in the mirror, bearing down on my immobilized Jeep.
I followed Miller’s advice: I didn’t panic. I did, however, drop any semblance of bravery, grab my iPhone with a clammy fist, and beg the hackers to make it stop.
Wireless Carjackers
This wasn’t the first time Miller and Valasek had put me behind the wheel of a compromised car. In the summer of 2013, I drove a Ford Escape and a Toyota Prius around a South Bend, Indiana, parking lot while they sat in the backseat with their laptops, cackling as they disabled my brakes, honked the horn, jerked the seat belt, and commandeered the steering wheel. “When you lose faith that a car will do what you tell it to do,” Miller observed at the time, “it really changes your whole view of how the thing works.” Back then, however, their hacks had a comforting limitation: The attacker’s PC had been wired into the vehicles’ onboard diagnostic port, a feature that normally gives repair technicians access to information about the car’s electronically controlled systems.
A mere two years later, that carjacking has gone wireless. Miller and Valasek plan to publish a portion of their exploit on the Internet, timed to a talk they’re giving at the Black Hat security conference in Las Vegas next month. It’s the latest in a series of revelations from the two hackers that have spooked the automotive industry and even helped to inspire legislation; WIRED has learned that senators Ed Markey and Richard Blumenthal plan to introduce an automotive security bill today to set new digital security standards for cars and trucks, first sparked when Markey took note of Miller and Valasek’s work in 2013.
As an auto-hacking antidote, the bill couldn’t be timelier. The attack tools Miller and Valasek developed can remotely trigger more than the dashboard and transmission tricks they used against me on the highway. They demonstrated as much on the same day as my traumatic experience on I-64; After narrowly averting death by semi-trailer, I managed to roll the lame Jeep down an exit ramp, re-engaged the transmission by turning the ignition off and on, and found an empty lot where I could safely continue the experiment.
Miller and Valasek’s full arsenal includes functions that at lower speeds fully kill the engine, abruptly engage the brakes, or disable them altogether. The most disturbing maneuver came when they cut the Jeep’s brakes, leaving me frantically pumping the pedal as the 2-ton SUV slid uncontrollably into a ditch. The researchers say they’re working on perfecting their steering control—for now they can only hijack the wheel when the Jeep is in reverse. Their hack enables surveillance too: They can track a targeted Jeep’s GPS coordinates, measure its speed, and even drop pins on a map to trace its route.
Click to Open Overlay GalleryAll of this is possible only because Chrysler, like practically all carmakers, is doing its best to turn the modern automobile into a smartphone. Uconnect, an Internet-connected computer feature in hundreds of thousands of Fiat Chrysler cars, SUVs, and trucks, controls the vehicle’s entertainment and navigation, enables phone calls, and even offers a Wi-Fi hot spot. And thanks to one vulnerable element, which Miller and Valasek won’t identify until their Black Hat talk, Uconnect’s cellular connection also lets anyone who knows the car’s IP address gain access from anywhere in the country. “From an attacker’s perspective, it’s a super nice vulnerability,” Miller says.
From that entry point, Miller and Valasek’s attack pivots to an adjacent chip in the car’s head unit—the hardware for its entertainment system—silently rewriting the chip’s firmware to plant their code. That rewritten firmware is capable of sending commands through the car’s internal computer network, known as a CAN bus, to its physical components like the engine and wheels. Miller and Valasek say the attack on the entertainment system seems to work on any Chrysler vehicle with Uconnect from late 2013, all of 2014, and early 2015. They’ve only tested their full set of physical hacks, including ones targeting transmission and braking systems, on a Jeep Cherokee, though they believe that most of their attacks could be tweaked to work on any Chrysler vehicle with the vulnerable Uconnect head unit. They have yet to try remotely hacking into other makes and models of cars.
After the researchers reveal the details of their work in Vegas, only two things will prevent their tool from enabling a wave of attacks on Jeeps around the world. First, they plan to leave out the part of the attack that rewrites the chip’s firmware; hackers following in their footsteps will have to reverse-engineer that element, a process that took Miller and Valasek months. But the code they publish will enable many of the dashboard hijinks they demonstrated on me as well as GPS tracking.
Second, Miller and Valasek have been sharing their research with Chrysler for nearly nine months, enabling the company to quietly release a patch ahead of the Black Hat conference. On July 16, owners of vehicles with the Uconnect feature were notified of the patch in a post on Chrysler’s websitethat didn’t offer any details or acknowledge Miller and Valasek’s research. “[Fiat Chrysler Automobiles] has a program in place to continuously test vehicles systems to identify vulnerabilities and develop solutions,” reads a statement a Chrysler spokesperson sent to WIRED. “FCA is committed to providing customers with the latest software updates to secure vehicles against any potential vulnerability.”
If consumers don’t realize this is an issue, they should, and they should start complaining to carmakers. This might be the kind of software bug most likely to kill someone.CHARLIE MILLER
Unfortunately, Chrysler’s patch must be manually implemented via a USB stick or by a dealership mechanic. (Download the update here.) That means many—if not most—of the vulnerable Jeeps will likely stay vulnerable.
Chrysler stated in a response to questions from WIRED that it “appreciates” Miller and Valasek’s work. But the company also seemed leery of their decision to publish part of their exploit. “Under no circumstances does FCA condone or believe it’s appropriate to disclose ‘how-to information’ that would potentially encourage, or help enable hackers to gain unauthorized and unlawful access to vehicle systems,” the company’s statement reads. “We appreciate the contributions of cybersecurity advocates to augment the industry’s understanding of potential vulnerabilities. However, we caution advocates that in the pursuit of improved public safety they not, in fact, compromise public safety.”
The two researchers say that even if their code makes it easier for malicious hackers to attack unpatched Jeeps, the release is nonetheless warranted because it allows their work to be proven through peer review. It also sends a message: Automakers need to be held accountable for their vehicles’ digital security. “If consumers don’t realize this is an issue, they should, and they should start complaining to carmakers,” Miller says. “This might be the kind of software bug most likely to kill someone.”
In fact, Miller and Valasek aren’t the first to hack a car over the Internet. In 2011 a team of researchers from the University of Washington and the University of California at San Diego showed that they could wirelessly disable the locks and brakes on a sedan. But those academics took a more discreet approach, keeping the identity of the hacked car secret and sharing the details of the exploit only with carmakers.
Miller and Valasek represent the second act in a good-cop/bad-cop routine. Carmakers who failed to heed polite warnings in 2011 now face the possibility of a public dump of their vehicles’ security flaws. The result could be product recalls or even civil suits, says UCSD computer science professor Stefan Savage, who worked on the 2011 study. Earlier this month, in fact, Range Rover issued a recall to fix a software security flaw that could be used to unlock vehicles’ doors. “Imagine going up against a class-action lawyer after Anonymous decides it would be fun to brick all the Jeep Cherokees in California,” Savage says.
For the auto industry and its watchdogs, in other words, Miller and Valasek’s release may be the last warning before they see a full-blown zero-day attack. “The regulators and the industry can no longer count on the idea that exploit code won’t be in the wild,” Savage says. “They’ve been thinking it wasn’t an imminent danger you needed to deal with. That implicit assumption is now dead.”
471,000 Hackable Automobiles
Click to Open Overlay GallerySitting on a leather couch in Miller’s living room as a summer storm thunders outside, the two researchers scan the Internet for victims.
Uconnect computers are linked to the Internet by Sprint’s cellular network, and only other Sprint devices can talk to them. So Miller has a cheap Kyocera Android phone connected to his battered MacBook. He’s using the burner phone as a Wi-Fi hot spot, scouring for targets using its thin 3G bandwidth.
A set of GPS coordinates, along with a vehicle identification number, make, model, and IP address, appears on the laptop screen. It’s a Dodge Ram. Miller plugs its GPS coordinates into Google Maps to reveal that it’s cruising down a highway in Texarkana, Texas. He keeps scanning, and the next vehicle to appear on his screen is a Jeep Cherokee driving around a highway cloverleaf between San Diego and Anaheim, California. Then he locates a Dodge Durango, moving along a rural road somewhere in the Upper Peninsula of Michigan. When I ask him to keep scanning, he hesitates. Seeing the actual, mapped locations of these unwitting strangers’ vehicles—and knowing that each one is vulnerable to their remote attack—unsettles him.
When Miller and Valasek first found the Uconnect flaw, they thought it might only enable attacks over a direct Wi-Fi link, confining its range to a few dozen yards. When they discovered the Uconnect’s cellular vulnerability earlier this summer, they still thought it might work only on vehicles on the same cell tower as their scanning phone, restricting the range of the attack to a few dozen miles. But they quickly found even that wasn’t the limit. “When I saw we could do it anywhere, over the Internet, I freaked out,” Valasek says. “I was frightened. It was like, holy fuck, that’s a vehicle on a highway in the middle of the country. Car hacking got real, right then.”
That moment was the culmination of almost three years of work. In the fall of 2012, Miller, a security researcher for Twitter and a former NSA hacker, and Valasek, the director of vehicle security research at the consultancy IOActive, were inspired by the UCSD and University of Washington study to apply for a car-hacking research grant from Darpa. With the resulting $80,000, they bought a Toyota Prius and a Ford Escape. They spent the next year tearing the vehicles apart digitally and physically, mapping out their electronic control units, or ECUs—the computers that run practically every component of a modern car—and learning to speak the CAN network protocol that controls them.
When they demonstrated a wired-in attack on those vehicles at the DefCon hacker conference in 2013, though, Toyota, Ford, and others in the automotive industry downplayed the significance of their work, pointing out that the hack had required physical access to the vehicles. Toyota, in particular, argued that its systems were “robust and secure” against wireless attacks. “We didn’t have the impact with the manufacturers that we wanted,” Miller says. To get their attention, they’d need to find a way to hack a vehicle remotely.
Click to Open Overlay GallerySo the next year, they signed up for mechanic’s accounts on the websites of every major automaker and downloaded dozens of vehicles’ technical manuals and wiring diagrams. Using those specs, they rated 24 cars, SUVs, and trucks on three factors they thought might determine their vulnerability to hackers: How many and what types of radios connected the vehicle’s systems to the Internet; whether the Internet-connected computers were properly isolated from critical driving systems, and whether those critical systems had “cyberphysical” components—whether digital commands could trigger physical actions like turning the wheel or activating brakes.
Based on that study, they rated Jeep Cherokee the most hackable model. Cadillac’s Escalade and Infiniti’s Q50 didn’t fare much better; Miller and Valasek ranked them second- and third-most vulnerable. When WIRED told Infiniti that at least one of Miller and Valasek’s warnings had been borne out, the company responded in a statement that its engineers “look forward to the findings of this [new] study” and will “continue to integrate security features into our vehicles to protect against cyberattacks.” Cadillac emphasized in a written statement that the company has released a new Escalade since Miller and Valasek’s last study, but that cybersecurity is “an emerging area in which we are devoting more resources and tools,” including the recent hire of a chief product cybersecurity officer.
After Miller and Valasek decided to focus on the Jeep Cherokee in 2014, it took them another year of hunting for hackable bugs and reverse-engineering to prove their educated guess. It wasn’t until June that Valasek issued a command from his laptop in Pittsburgh and turned on the windshield wipers of the Jeep in Miller’s St. Louis driveway.
Since then, Miller has scanned Sprint’s network multiple times for vulnerable vehicles and recorded their vehicle identification numbers. Plugging that data into an algorithm sometimes used for tagging and tracking wild animals to estimate their population size, he estimated that there are as many as 471,000 vehicles with vulnerable Uconnect systems on the road.
Pinpointing a vehicle belonging to a specific person isn’t easy. Miller and Valasek’s scans reveal random VINs, IP addresses, and GPS coordinates. Finding a particular victim’s vehicle out of thousands is unlikely through the slow and random probing of one Sprint-enabled phone. But enough phones scanning together, Miller says, could allow an individual to be found and targeted. Worse, he suggests, a skilled hacker could take over a group of Uconnect head units and use them to perform more scans—as with any collection of hijacked computers—worming from one dashboard to the next over Sprint’s network. The result would be a wirelessly controlled automotive botnet encompassing hundreds of thousands of vehicles.
“For all the critics in 2013 who said our work didn’t count because we were plugged into the dashboard,” Valasek says, “well, now what?”
Click to Open Overlay GalleryCongress Takes on Car Hacking
Now the auto industry needs to do the unglamorous, ongoing work of actually protecting cars from hackers. And Washington may be about to force the issue.
Later today, senators Markey and Blumenthal intend to reveal new legislation designed to tighten cars’ protections against hackers. The bill (which a Markey spokesperson insists wasn’t timed to this story) will call on the National Highway Traffic Safety Administration and the Federal Trade Commission to set new security standards and create a privacy and security rating system for consumers. “Controlled demonstrations show how frightening it would be to have a hacker take over controls of a car,” Markey wrote in a statement to WIRED. “Drivers shouldn’t have to choose between being connected and being protected…We need clear rules of the road that protect cars from hackers and American families from data trackers.”
Markey has keenly followed Miller and Valasek’s research for years. Citing their 2013 Darpa-funded research and hacking demo, he sent a letter to 20 automakers, asking them to answer a series of questions about their security practices. The answers, released in February, show what Markey describes as “a clear lack of appropriate security measures to protect drivers against hackers who may be able to take control of a vehicle.” Of the 16 automakers who responded, all confirmed that virtually every vehicle they sell has some sort of wireless connection, including Bluetooth, Wi-Fi, cellular service, and radios. (Markey didn’t reveal the automakers’ individual responses.) Only seven of the companies said they hired independent security firms to test their vehicles’ digital security. Only two said their vehicles had monitoring systems that checked their CAN networks for malicious digital commands.
UCSD’s Savage says the lesson of Miller and Valasek’s research isn’t that Jeeps or any other vehicle are particularly vulnerable, but that practicallyany modern vehicle could be vulnerable. “I don’t think there are qualitative differences in security between vehicles today,” he says. “The Europeans are a little bit ahead. The Japanese are a little bit behind. But broadly writ, this is something everyone’s still getting their hands around.”
Click to Open Overlay GalleryAside from wireless hacks used by thieves to open car doors, only one malicious car-hacking attack has been documented: In 2010 a disgruntled employee in Austin, Texas, used a remote shutdown system meant for enforcing timely car payments to brick more than 100 vehicles. But the opportunities for real-world car hacking have only grown, as automakers add wireless connections to vehicles’ internal networks. Uconnect is just one of a dozen telematics systems, including GM Onstar, Lexus Enform, Toyota Safety Connect, Hyundai Bluelink, and Infiniti Connection.
In fact, automakers are thinking about their digital security more than ever before, says Josh Corman, the cofounder of I Am the Cavalry, a security industry organization devoted to protecting future Internet-of-things targets like automobiles and medical devices. Thanks to Markey’s letter, and another set of questions sent to automakers by the House Energy and Commerce Committee in May, Corman says, Detroit has known for months that car security regulations are coming.
But Corman cautions that the same automakers have been more focused on competing with each other to install new Internet-connected cellular services for entertainment, navigation, and safety. (Payments for those services also provide a nice monthly revenue stream.) The result is that the companies have an incentive to add Internet-enabled features—but not to secure them from digital attacks. “They’re getting worse faster than they’re getting better,” he says. “If it takes a year to introduce a new hackable feature, then it takes them four to five years to protect it.”
Corman’s group has been visiting auto industry events to push five recommendations: safer design to reduce attack points, third-party testing, internal monitoring systems, segmented architecture to limit the damage from any successful penetration, and the same Internet-enabled security software updates that PCs now receive. The last of those in particular is already catching on; Ford announced a switch to over-the-air updates in March, and BMW used wireless updates to patch a hackable security flaw in door locks in January.
Corman says carmakers need to befriend hackers who expose flaws, rather than fear or antagonize them—just as companies like Microsoft have evolved from threatening hackers with lawsuits to inviting them to security conferences and paying them “bug bounties” for disclosing security vulnerabilities. For tech companies, Corman says, “that enlightenment took 15 to 20 years.” The auto industry can’t afford to take that long. “Given that my car can hurt me and my family,” he says, “I want to see that enlightenment happen in three to five years, especially since the consequences for failure are flesh and blood.”
As I drove the Jeep back toward Miller’s house from downtown St. Louis, however, the notion of car hacking hardly seemed like a threat that will wait three to five years to emerge. In fact, it seemed more like a matter of seconds; I felt the vehicle’s vulnerability, the nagging possibility that Miller and Valasek could cut the puppet’s strings again at any time.
The hackers holding the scissors agree. “We shut down your engine—a big rig was honking up on you because of something we did on our couch,” Miller says, as if I needed the reminder. “This is what everyone who thinks about car security has worried about for years. This is a reality.”
1Correction 10:45 7/21/2015: An earlier version of the story stated that the hacking demonstration took place on Interstate 40, when in fact it was Route 40, which coincides in St. Louis with Interstate 64.
http://www.wired.com/2015/07/hackers-remotely-kill-jeep-highway/
2012 Toyota Prius
2013 Honda Civic
2006 Chrysler Grand Caravan
www.wired.com/2010/03/hacker-bricks-cars/
www.autoguide.com/auto-news/2015/07/jeep-cherokee-uconnect-vulnerable-to-wireless-hacking.html
www.autoguide.com/auto-news/2015/02/automakers-fail-to-protect-cars-against-hackers-report.html
www.dailydot.com/technology/car-hack-jeep-uconnect-vulnerability/
www.theneeds.com/read/n8938526/jeep-cherokee-uconnect-vulnerable-to-wireless-hacking-autoguide
www.chrysler.com/en/mobile_apps/uconnect_mobile/
www.driveuconnect.com
MISRA C is a set of software development guidelines for the C programming language developed by MISRA (Motor Industry Software Reliability Association)
https://en.wikipedia.org/wiki/MISRA_C
Like computer networks, cars are becoming targets for hackers
ONE ingenious conceit employed to great effect by science-fiction writers is the sentient machine bent on pursuing an inner mission of its own, from HAL in “2001: A Space Odyssey” to V.I.K.I. in the film version of “I Robot”. Usually, humanity thwarts the rogue machine in question, but not always. In “Gridiron”, released in 1995, a computer system called Ismael—which controls the heating, lighting, lifts and everything else in a skyscraper in Los Angeles—runs amok and wreaks havoc on its occupants. The story’s cataclysmic conclusion involves Ismael instructing the skyscraper’s computer-controlled hydraulic shock-absorbers (installed to damp the swaying caused by earthquakes) to shake the building, literally, to pieces. As it does so, Ismael’s cyber-spirit flees the crumbling tower by e-mailing a copy of its malevolent code to a diaspora of like-minded computers elsewhere in the world.
While vengeful cyber-spirits may not lurk inside today’s buildings or machines, malevolent humans frequently do. Taking control remotely of modern cars, for instance, has become distressingly easy for hackers, given the proliferation of wireless-connected processors now used to run everything from keyless entry and engine ignition to brakes, steering, tyre pressure, throttle setting, transmission and anti-collision systems. Today’s vehicles have anything from 20 to 100 electronic control units (ECUs) managing their various electro-mechanical systems. Without adequate protection, the “connected car” can be every bit as vulnerable to attack and subversion as any computer network.
Were that not worrisome enough, motorists can expect further cyber-mischief once vehicle-to-vehicle (V2V) communication becomes prevalent, and cars are endowed with their own IP addresses and internet connections. Meanwhile, car makers are beginning to offer over-the-air updates, using cellular connections, for patching flaws in their vehicles’ software. This makes it easier for attackers to infiltrate not just the odd vehicle, but thousands of them at a time. BMW recently beamed an over-the-air software update to 2.2m of its customers’ cars. The potential for fleet-wide cyber-attacks ought to have carmakers seriously concerned.
Nor is it just vehicle theft motorists have to worry about. Car hacking can threaten people’s lives, both in the vehicle and outside it. The mind shudders at the thought of malicious code being inserted remotely into the logic of a self-driving car speeding autonomously down the highway.
This is not science fiction. Land Rover recently demonstrated a smartphone app that lets an owner take wireless control of his machine while up to ten metres (33 feet) away from it. The aim, says Land Rover, is to let off-road drivers manoeuvre their vehicles safely over dangerous stretches of terrain, or to assist urban motorists trying to back a vehicle out of a tight parking spot. Fine, except that such a level of remote control could also make it easier for thieves to steal parked cars, or terrorists to create chaos on the road.
What is being done to protect vehicles from cyber-attack? Several recent events have stirred legislators into action. Last summer, for instance, during a meeting of automotive engineers and security experts, a 14-year-old schoolboy showed industry experts how to take control of a car remotely using circuitry he had lashed up overnight with $15 worth of parts bought from Radio Shack the day before. The youngster turned the windscreen wipers on and off, locked and unlocked the doors, engaged the engine-start mechanism, and had the headlamps flash to the beat of a tune on his iPhone. “It was mind-blowing,” recounted Andrew Brown, vice-president and chief technologist at Delphi Automotive, a manufacturer of auto parts.
More recently, Consumer Reports, a publication owned by a consumer advocacy and independent testing centre in Yonkers, New York, got an eye-opener during a visit to a National Highway Traffic Safety Administration (NHTSA) laboratory. The publication’s editors were surprised when a technician turned off the engine of a test car they were driving using nothing more than a mobile phone. NHTSA has found ways of tampering remotely with door locks, seat-belt tensioners, instrument panels, brakes, steering mechanisms and engines—all while the test cars were being driven. Since its laboratory visit, Consumer Reports has been urging America’s Congress to legislate for the highest possible security standards for car computer systems.
The message seems to be getting through. In recent weeks, the House Committee on Energy and Commerce has questioned all 17 motor manufacturers that sell vehicles in America, as well as NHTSA itself, about their plans to thwart car hackers. For its part, NHTSA has compiled a 40-page report on how best to deal with cyber-threats on the road. The safety agency has shared its findings with carmakers, but has been understandably reluctant to publicise the counter-measures in detail.
The problem confronting carmakers everywhere is that, as they add ever more ECUs to their vehicles, to provide more features and convenience for motorists, they unwittingly expand the “attack surface” of their on-board systems. In security terms, this attack surface—the exposure a system presents in terms of its reachable and exploitable vulnerabilities—determines the ease, or otherwise, with which hackers can take control of a system.
In a car, the remote attack surface includes such things as the vehicle’s on-board diagnostics, Bluetooth and WiFi ports, telematic devices like GPS navigation and cellular radios, plus radio-frequency chips in remote entry keys, tyre pressure sensors and the like that communicate wirelessly with transponders connected to the vehicle’s Controller Area Network (CAN).
By functioning as a common communications bus, the CAN’s two-wire network for transmitting digital messages around a vehicle allows manufacturers to add features and accessories to a vehicle simply by plugging the additional components into the bus, instead of having to run fresh wires or install additional networks. That makes wiring the innards of cars easier and cheaper.
But by multiplexing signals from different devices on the CAN’s common communications channel, it is possible for vulnerabilities associated with an attack surface to talk to components that perform actual driving functions. For instance, it is not far-fetched to imagine an on-board cellular connection (such as GM’s OnStar network) being tricked into allowing hackers to inject malicious code into ECUs managing, say, the steering, braking or engine controls—courtesy of the shared CAN bus.
By far the best study to date of vehicle security is a survey carried out by Charlie Miller, formerly with the National Security Agency and now at Twitter, and Chris Valasek of IOActive, a security services company based in Seattle. The two researchers examined the remote attack surfaces of 20 popular models on American roads. In each case, they traced the network architecture along with all the computer-controlled features of the vehicles involved. In doing so, they were able to draw conclusions about how vulnerable, in principle, the various vehicles were to remote attack.
Of the half dozen attack surfaces Dr Miller and Mr Valasek analysed in detail for each vehicle, the most vulnerable in all instances turned out to be the on-board Bluetooth feature (“a very reliable entry point for attackers”), a car’s cellular radio service (“the holy grail of automotive attack”), and any browser-based internet connection available (“widely understood by attackers”).
The three most hackable vehicles—in terms of how their network architectures permitted attack surfaces to talk to components performing physical actions—were the 2014 Jeep Cherokee, the 2015 Cadillac Escalade and the 2014 Infiniti Q50. This being litigious America, the automakers concerned quickly found themselves in the legal cross-hairs, as owners sought financial compensation for their vehicles’ perceived vulnerabilities.
One conclusion of the study is that, like computer networks, vehicles need layered defences, so that penetrating to the heart of the system, though not impossible, becomes increasingly tedious and costly for an attacker. Another obvious suggestion is that automotive networks like the CAN bus, along with its local interconnections, should be designed in a way that isolates ECUs that talk to the outside world from those that control critical functions within the vehicle.
Ultimately, of course, cars are going to need some method of detecting cyber-attacks, and to have the means to neutralise them. In one important way, threat detection is easier in cars than in the networks used in offices. On a CAN bus, for instance, only ECUs are engaged in swapping messages with one another; no gullible humans are involved—as they are in offices—to open back doors unwittingly to phishing attacks from cyber-crooks masquerading as colleagues or customers.
That makes it easier to spot anomalies caused by an attacker’s injected code. To capture the attention of a targeted ECU, a bogus message has to be sent at a much higher rate—anything up to 100 times normal—in order to swamp legitimate messages being received by the processor. A simple device that plugs into a car’s diagnostic port can easily detect such exceptional traffic and instruct the CAN bus to ditch it.
That is a good start. But it does not mean cars can be made immune to cyber-attack. There is no such thing as absolute security. As Dr Miller and Mr Valasek note, even firms like Microsoft and Google have been unable to make a web browser that cannot go a few months without needing some critical security patch. Cars are no different. All the more so once they start communicating with one another, as well as with traffic signs and other roadside equipment. Welcome to the scary world of the computerised car on the connected highway.
