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Research shows how MacBook Webcams can spy on their users without warning

washingtonpost.com

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Re: Research shows how MacBook Webcams can spy on their users without warning

#231

Post by theshrike79 »

kro0ub wrote: post #211
Guvante wrote: post #188

Earlier quoted context omitted.

They basically did, the light can only be turned off when the USB signals "standby". The hack is to override the camera to ignore that signal. It is a rather unique idea and probably not something anyone even considered at Apple.

So is an MBP/A running Linux susceptible to the hack, then?

As far as I can tell, yes. The hack is about rewriting the camera controller chip, which isn't platform specific in any way.

OS X allows non-privileged users to do that for some reason though...

Re: Research shows how MacBook Webcams can spy on their users without warning

#232

Post by sigkill »

codygman wrote: post #212
ancarda wrote: post #170

Earlier quoted context omitted.

Recent versions of iOS ask for permission to use the microphone.

What if in the case of a "lawful intercept" iOS does not ask for permission?

The beauty of your comment is that just a little over half a year ago you'd be considered a complete conspiracy nut and a paranoid tinfoil hatter but today there's no one even saying anything against you.

Re: Research shows how MacBook Webcams can spy on their users without warning

#233

Post by kro0ub »

theshrike79 wrote: post #231
kro0ub wrote: post #211

Earlier quoted context omitted.

So is an MBP/A running Linux susceptible to the hack, then?

As far as I can tell, yes. The hack is about rewriting the camera controller chip, which isn't platform specific in any way. OS X allows non-privileged users to do that for some reason though...

Is it possible to un-hack your cam controller chip, then?

Re: Research shows how MacBook Webcams can spy on their users without warning

#234

Post by lewispollard »

falcolas wrote: post #72
headgasket wrote: post #65

Earlier quoted context omitted.

plug a square card reader in the jack.

Doesn't physically turn off the internal microphone. I've found out the hard way: I have a headset with a hardware mic switch. If this switch is in the "off" position when headphones are put into the jack, the mic built into my mac still operates. This is with a mid-2012 macbook model.

You can, for example, set up an aggregate audio device in the audio input/output config panel to enable all inputs and outputs to work at the same time. So it's not unreasonable to think that the internal mic could be activated even with something plugged into the jack.

Re: Research shows how MacBook Webcams can spy on their users without warning

#235

Post by kvinnako »

winstonx wrote: post #151
justin66 wrote: post #98

Earlier quoted context omitted.

> Having an inline LED is still a bit over-engineered in my opinion. Overengineering usually refers to something that's not simple or elegant or a solution which represents more effort than the problem calls for. None of those factors seem to apply here.

A blinking light requires electricity. The sliding cover is purely mechanical, tamper evident, and requires physical access to hack. The sliding cover is simpler and more secure.

Well, Ideally I wouldn't want to keep opening and closing the slide up and down. So this is simpler but not nearly that useful. Apple strives to be secure and easy to use. That's why the top dollar for apple products.

Re: Research shows how MacBook Webcams can spy on their users without warning

#236

Post by cinquemb »

lewispollard wrote: post #234
falcolas wrote: post #72

Earlier quoted context omitted.

Doesn't physically turn off the internal microphone. I've found out the hard way: I have a headset with a hardware mic switch. If this switch is in the "off" position when headphones are put into the jack, the mic built into my mac still operates. This is with a mid-2012 macbook model.

You can, for example, set up an aggregate audio device in the audio input/output config panel to enable all inputs and outputs to work at the same time. So it's not unreasonable to think that the internal mic could be activated even with something plugged into the jack.

Well I was playing around a bit more, and I was able to disable the(or a, not sure how many are in 2010 MBPs) internal mic by taking an old audio input jack (cutting the wires), plugging it in (so it looks like a nub sticking out), going to the audio settings and setting the audio port from "Sound Output" to "Sound Input" and the internal mic picked up no readings. Still trying to figure out how to do that from the command line.

Re: Research shows how MacBook Webcams can spy on their users without warning

#237

Post by superuser2 »

greglindahl wrote: post #134
superuser2 wrote: post #53

Earlier quoted context omitted.

Does tape actually provide enough impedance to prevent surveillance through your microphones? Seems like all an attacker would have to do is amplify (and possibly filter) the audio a bit.

I turned up the mic all the way, did a skype test call. I could hear myself if I shouted (input level=0). If I talked at a normal volume level, it was audible (and the input level showed as 2/15. I might try a couple of layers of tape... EDIT: Yeah, 2nd layer of tape = 0 input level even if I shout really, really loudly. You can't imagine how much my coworkers are enjoying this experimentation!

Skype has a noise gate - any play on the microphone below a certain level is cut off. Someone with direct access to your microphone can listen without the noise gate and might still hear.

Re: Research shows how MacBook Webcams can spy on their users without warning

#238

Post by lawnchair_larry »

shabble wrote: post #209
lawnchair_larry wrote: post #192

Earlier quoted context omitted.

Not really what I'm looking for.

It's increasingly common in modern ICs (SoCs and microcontrollers especially) to have only the minimum required connections be permanently assigned to physical pins. The rest of the pins are connected to some routing logic which in turn connects to the various chip internal signals. This is great in board design because you can often simplify PCB routing by reassigning pins as you need them for your layout, rather th…

Thanks, that's informative.

Re: Research shows how MacBook Webcams can spy on their users without warning

#239

Post by kyzyl »

lake99 wrote: post #160
kyzyl wrote: post #36

Earlier quoted context omitted.

If you have the LED hooked up in parallel with the chip, then you can't really do any fancy indication things like blink the LED, change colour (voltage level) etc. It's possible that the engineers wanted to maintain that flexibility. Second, if the LED fails to a short your camera won't get any power. That means an expensive component appears to be broken when it's only a very cheap component, and you have no way to…

> Second, if the LED fails to a short your camera won't get any power. One never puts an LED on the power line directly. That will certainly blow up most LEDs. Power rails are typically 5V or 3.3V. LED drop is about 1V (+/- 0.3, varies between part numbers). There is always a resistor in series with the LED, to drop the rest of the voltage, and limit the current. So, LED getting shorted is not a problem. This is the…

Sorry I didn't check back here for a couple days.

> There is always a resistor in series with the LED

Sure, almost always. But there are many different voltage level, forward drop, forward current combinations for a given application. There's no guarantee, even with a ballast resistor, that the a shorted LED won't result in an effective short to the power rail (not a real short, but drawing close to the power supply's current sourcing limit). A resistor with a shorted LED results in a useless current sink, in any case.

> But how often have you seen these tiny LEDs fail...I have never ever seen it happen.

What you've seen or not seen has very little bearing on the reality that parts fail. Period. Things should be designed in a cost effective way that minimizes the possibility/effects of failures. FWIW, I had a laptop recently that had a dead LED on the front panel :-/

> There is always a resistor in series with the LED

I just meant that if your "power rail" is actually just a signal line (or whatever) for some other purpose, and the led is there to indicate activity, then even in "low" signal states where the LED isn't fully conducting yet there is a small leakage current.

Re: Research shows how MacBook Webcams can spy on their users without warning

#240

Post by winstonx »

madeofpalk wrote: post #213
unwind wrote: post #193

Earlier quoted context omitted.

A mechanical sliding piece of material without any electrical components at all must be considered simpler (and thus "less engineered") than an LED, mustn't it? I would be way easier to convince that a piece of plastic is harder to hack than a LED. For instance, there would be no embedded microcontroller to subvert. Also, USB is a bus , you can't splice an LED into the power line of the USB going to a camera and conc…

> A mechanical sliding piece of material without any electrical components at all must be considered simpler (and thus "less engineered") than an LED, mustn't it? Looking at my current macbook lid, I don't how how that would physically fit. The camera would need to be recessed further into the lid to accomodate for the door. > I would be way easier to convince that a piece of plastic is harder to hack than a LED. For…

This cover fits great over my macbook camera http://www.amazon.com/C-Slide-1-0-Webcam-Cover/dp/B00AZ639VG
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