Avi Rubin: All your devices can be hacked

43,672 views ・ 2015-07-15

TED


Please double-click on the English subtitles below to play the video.

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Translator: Joseph Geni Reviewer: Morton Bast
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I'm a computer science professor,
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and my area of expertise is
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computer and information security.
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When I was in graduate school,
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I had the opportunity to overhear my grandmother
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describing to one of her fellow senior citizens
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what I did for a living.
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Apparently, I was in charge of making sure that
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no one stole the computers from the university. (Laughter)
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And, you know, that's a perfectly reasonable thing
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for her to think, because I told her I was working
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in computer security,
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and it was interesting to get her perspective.
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But that's not the most ridiculous thing I've ever heard
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anyone say about my work.
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The most ridiculous thing I ever heard is,
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I was at a dinner party, and a woman heard
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that I work in computer security,
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and she asked me if -- she said her computer had been
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infected by a virus, and she was very concerned that she
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might get sick from it, that she could get this virus. (Laughter)
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And I'm not a doctor, but I reassured her
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that it was very, very unlikely that this would happen,
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but if she felt more comfortable, she could be free to use
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latex gloves when she was on the computer,
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and there would be no harm whatsoever in that.
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I'm going to get back to this notion of being able to get
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a virus from your computer, in a serious way.
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What I'm going to talk to you about today
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are some hacks, some real world cyberattacks that people
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in my community, the academic research community,
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have performed, which I don't think
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most people know about,
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and I think they're very interesting and scary,
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and this talk is kind of a greatest hits
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of the academic security community's hacks.
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None of the work is my work. It's all work
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that my colleagues have done, and I actually asked them
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for their slides and incorporated them into this talk.
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So the first one I'm going to talk about
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are implanted medical devices.
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Now medical devices have come a long way technologically.
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You can see in 1926 the first pacemaker was invented.
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1960, the first internal pacemaker was implanted,
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hopefully a little smaller than that one that you see there,
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and the technology has continued to move forward.
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In 2006, we hit an important milestone from the perspective
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of computer security.
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And why do I say that?
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Because that's when implanted devices inside of people
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started to have networking capabilities.
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One thing that brings us close to home is we look
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at Dick Cheney's device, he had a device that
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pumped blood from an aorta to another part of the heart,
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and as you can see at the bottom there,
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it was controlled by a computer controller,
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and if you ever thought that software liability
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was very important, get one of these inside of you.
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Now what a research team did was they got their hands
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on what's called an ICD.
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This is a defibrillator, and this is a device
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that goes into a person to control their heart rhythm,
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and these have saved many lives.
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Well, in order to not have to open up the person
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every time you want to reprogram their device
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or do some diagnostics on it, they made the thing be able
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to communicate wirelessly, and what this research team did
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is they reverse engineered the wireless protocol,
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and they built the device you see pictured here,
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with a little antenna, that could talk the protocol
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to the device, and thus control it.
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In order to make their experience real -- they were unable
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to find any volunteers, and so they went
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and they got some ground beef and some bacon
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and they wrapped it all up to about the size
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of a human being's area where the device would go,
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and they stuck the device inside it
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to perform their experiment somewhat realistically.
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They launched many, many successful attacks.
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One that I'll highlight here is changing the patient's name.
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I don't know why you would want to do that,
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but I sure wouldn't want that done to me.
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And they were able to change therapies,
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including disabling the device -- and this is with a real,
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commercial, off-the-shelf device --
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simply by performing reverse engineering and sending
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wireless signals to it.
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There was a piece on NPR that some of these ICDs
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could actually have their performance disrupted
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simply by holding a pair of headphones onto them.
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Now, wireless and the Internet
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can improve health care greatly.
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There's several examples up on the screen
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of situations where doctors are looking to implant devices
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inside of people, and all of these devices now,
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it's standard that they communicate wirelessly,
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and I think this is great,
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but without a full understanding of trustworthy computing,
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and without understanding what attackers can do
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and the security risks from the beginning,
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there's a lot of danger in this.
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Okay, let me shift gears and show you another target.
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I'm going to show you a few different targets like this,
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and that's my talk. So we'll look at automobiles.
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This is a car, and it has a lot of components,
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a lot of electronics in it today.
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In fact, it's got many, many different computers inside of it,
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more Pentiums than my lab did when I was in college,
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and they're connected by a wired network.
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There's also a wireless network in the car,
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which can be reached from many different ways.
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So there's Bluetooth, there's the FM and XM radio,
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there's actually wi-fi, there's sensors in the wheels
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that wirelessly communicate the tire pressure
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to a controller on board.
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The modern car is a sophisticated multi-computer device.
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And what happens if somebody wanted to attack this?
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Well, that's what the researchers
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that I'm going to talk about today did.
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They basically stuck an attacker on the wired network
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and on the wireless network.
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Now, they have two areas they can attack.
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One is short-range wireless, where you can actually
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communicate with the device from nearby,
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either through Bluetooth or wi-fi,
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and the other is long-range, where you can communicate
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with the car through the cellular network,
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or through one of the radio stations.
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Think about it. When a car receives a radio signal,
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it's processed by software.
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That software has to receive and decode the radio signal,
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and then figure out what to do with it,
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even if it's just music that it needs to play on the radio,
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and that software that does that decoding,
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if it has any bugs in it, could create a vulnerability
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for somebody to hack the car.
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The way that the researchers did this work is,
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they read the software in the computer chips
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that were in the car, and then they used sophisticated
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reverse engineering tools
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to figure out what that software did,
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and then they found vulnerabilities in that software,
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and then they built exploits to exploit those.
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They actually carried out their attack in real life.
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They bought two cars, and I guess
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they have better budgets than I do.
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The first threat model was to see what someone could do
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if an attacker actually got access
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to the internal network on the car.
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Okay, so think of that as, someone gets to go to your car,
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they get to mess around with it, and then they leave,
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and now, what kind of trouble are you in?
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The other threat model is that they contact you
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in real time over one of the wireless networks
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like the cellular, or something like that,
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never having actually gotten physical access to your car.
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This is what their setup looks like for the first model,
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where you get to have access to the car.
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They put a laptop, and they connected to the diagnostic unit
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on the in-car network, and they did all kinds of silly things,
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like here's a picture of the speedometer
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showing 140 miles an hour when the car's in park.
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Once you have control of the car's computers,
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you can do anything.
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Now you might say, "Okay, that's silly."
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Well, what if you make the car always say
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it's going 20 miles an hour slower than it's actually going?
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You might produce a lot of speeding tickets.
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Then they went out to an abandoned airstrip with two cars,
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the target victim car and the chase car,
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and they launched a bunch of other attacks.
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One of the things they were able to do from the chase car
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is apply the brakes on the other car,
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simply by hacking the computer.
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They were able to disable the brakes.
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They also were able to install malware that wouldn't kick in
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and wouldn't trigger until the car was doing something like
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going over 20 miles an hour, or something like that.
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The results are astonishing, and when they gave this talk,
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even though they gave this talk at a conference
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to a bunch of computer security researchers,
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everybody was gasping.
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They were able to take over a bunch of critical computers
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inside the car: the brakes computer, the lighting computer,
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the engine, the dash, the radio, etc.,
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and they were able to perform these on real commercial
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cars that they purchased using the radio network.
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They were able to compromise every single one of the
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pieces of software that controlled every single one
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of the wireless capabilities of the car.
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All of these were implemented successfully.
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How would you steal a car in this model?
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Well, you compromise the car by a buffer overflow
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of vulnerability in the software, something like that.
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You use the GPS in the car to locate it.
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You remotely unlock the doors through the computer
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that controls that, start the engine, bypass anti-theft,
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and you've got yourself a car.
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Surveillance was really interesting.
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The authors of the study have a video where they show
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themselves taking over a car and then turning on
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the microphone in the car, and listening in on the car
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while tracking it via GPS on a map,
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and so that's something that the drivers of the car
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would never know was happening.
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Am I scaring you yet?
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I've got a few more of these interesting ones.
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These are ones where I went to a conference,
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and my mind was just blown, and I said,
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"I have to share this with other people."
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This was Fabian Monrose's lab
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at the University of North Carolina, and what they did was
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something intuitive once you see it,
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but kind of surprising.
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They videotaped people on a bus,
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and then they post-processed the video.
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What you see here in number one is a
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reflection in somebody's glasses of the smartphone
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that they're typing in.
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They wrote software to stabilize --
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even though they were on a bus
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and maybe someone's holding their phone at an angle --
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to stabilize the phone, process it, and
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you may know on your smartphone, when you type
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a password, the keys pop out a little bit, and they were able
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to use that to reconstruct what the person was typing,
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and had a language model for detecting typing.
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What was interesting is, by videotaping on a bus,
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they were able to produce exactly what people
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on their smartphones were typing,
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and then they had a surprising result, which is that
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their software had not only done it for their target,
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but other people who accidentally happened
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to be in the picture, they were able to produce
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what those people had been typing, and that was kind of
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an accidental artifact of what their software was doing.
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I'll show you two more. One is P25 radios.
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P25 radios are used by law enforcement
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and all kinds of government agencies
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and people in combat to communicate,
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and there's an encryption option on these phones.
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This is what the phone looks like. It's not really a phone.
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It's more of a two-way radio.
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Motorola makes the most widely used one, and you can see
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that they're used by Secret Service, they're used in combat,
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it's a very, very common standard in the U.S. and elsewhere.
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So one question the researchers asked themselves is,
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could you block this thing, right?
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Could you run a denial-of-service,
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because these are first responders?
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So, would a terrorist organization want to black out the
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ability of police and fire to communicate at an emergency?
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They found that there's this GirlTech device used for texting
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that happens to operate at the same exact frequency
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as the P25, and they built what they called
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My First Jammer. (Laughter)
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If you look closely at this device,
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it's got a switch for encryption or cleartext.
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Let me advance the slide, and now I'll go back.
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You see the difference?
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This is plain text. This is encrypted.
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There's one little dot that shows up on the screen,
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and one little tiny turn of the switch.
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And so the researchers asked themselves, "I wonder how
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many times very secure, important, sensitive conversations
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are happening on these two-way radios where they forget
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to encrypt and they don't notice that they didn't encrypt?"
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So they bought a scanner. These are perfectly legal
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and they run at the frequency of the P25,
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and what they did is they hopped around frequencies
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and they wrote software to listen in.
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If they found encrypted communication, they stayed
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on that channel and they wrote down, that's a channel
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that these people communicate in,
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these law enforcement agencies,
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and they went to 20 metropolitan areas and listened in
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on conversations that were happening at those frequencies.
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They found that in every metropolitan area,
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they would capture over 20 minutes a day
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of cleartext communication.
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And what kind of things were people talking about?
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Well, they found the names and information
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about confidential informants. They found information
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that was being recorded in wiretaps,
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a bunch of crimes that were being discussed,
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sensitive information.
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It was mostly law enforcement and criminal.
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They went and reported this to the law enforcement
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agencies, after anonymizing it,
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and the vulnerability here is simply the user interface
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wasn't good enough. If you're talking
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about something really secure and sensitive, it should
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be really clear to you that this conversation is encrypted.
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That one's pretty easy to fix.
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The last one I thought was really, really cool,
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and I just had to show it to you, it's probably not something
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that you're going to lose sleep over
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like the cars or the defibrillators,
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but it's stealing keystrokes.
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Now, we've all looked at smartphones upside down.
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Every security expert wants to hack a smartphone,
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and we tend to look at the USB port, the GPS for tracking,
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the camera, the microphone, but no one up till this point
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had looked at the accelerometer.
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The accelerometer is the thing that determines
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the vertical orientation of the smartphone.
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And so they had a simple setup.
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They put a smartphone next to a keyboard,
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and they had people type, and then their goal was
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to use the vibrations that were created by typing
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to measure the change in the accelerometer reading
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to determine what the person had been typing.
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Now, when they tried this on an iPhone 3GS,
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this is a graph of the perturbations that were created
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by the typing, and you can see that it's very difficult
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to tell when somebody was typing or what they were typing,
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but the iPhone 4 greatly improved the accelerometer,
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and so the same measurement
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produced this graph.
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Now that gave you a lot of information while someone
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was typing, and what they did then is used advanced
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artificial intelligence techniques called machine learning
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to have a training phase,
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and so they got most likely grad students
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to type in a whole lot of things, and to learn,
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to have the system use the machine learning tools that
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were available to learn what it is that the people were typing
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and to match that up
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with the measurements in the accelerometer.
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And then there's the attack phase, where you get
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somebody to type something in, you don't know what it was,
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but you use your model that you created
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in the training phase to figure out what they were typing.
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They had pretty good success. This is an article from the USA Today.
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They typed in, "The Illinois Supreme Court has ruled
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that Rahm Emanuel is eligible to run for Mayor of Chicago"
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— see, I tied it in to the last talk —
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"and ordered him to stay on the ballot."
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Now, the system is interesting, because it produced
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"Illinois Supreme" and then it wasn't sure.
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The model produced a bunch of options,
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and this is the beauty of some of the A.I. techniques,
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is that computers are good at some things,
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humans are good at other things,
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take the best of both and let the humans solve this one.
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Don't waste computer cycles.
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A human's not going to think it's the Supreme might.
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It's the Supreme Court, right?
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And so, together we're able to reproduce typing
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simply by measuring the accelerometer.
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Why does this matter? Well, in the Android platform,
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for example, the developers have a manifest
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where every device on there, the microphone, etc.,
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has to register if you're going to use it
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so that hackers can't take over it,
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but nobody controls the accelerometer.
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So what's the point? You can leave your iPhone next to
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someone's keyboard, and just leave the room,
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and then later recover what they did,
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even without using the microphone.
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If someone is able to put malware on your iPhone,
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they could then maybe get the typing that you do
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whenever you put your iPhone next to your keyboard.
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There's several other notable attacks that unfortunately
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I don't have time to go into, but the one that I wanted
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to point out was a group from the University of Michigan
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which was able to take voting machines,
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the Sequoia AVC Edge DREs that
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were going to be used in New Jersey in the election
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that were left in a hallway, and put Pac-Man on it.
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So they ran the Pac-Man game.
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What does this all mean?
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Well, I think that society tends to adopt technology
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really quickly. I love the next coolest gadget.
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But it's very important, and these researchers are showing,
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that the developers of these things
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need to take security into account from the very beginning,
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and need to realize that they may have a threat model,
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16:29
but the attackers may not be nice enough
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to limit themselves to that threat model,
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and so you need to think outside of the box.
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What we can do is be aware
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that devices can be compromised,
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and anything that has software in it
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is going to be vulnerable. It's going to have bugs.
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Thank you very much. (Applause)
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