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Apple's T2 chip will prevent hackers from eavesdropping on your microphone

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Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#121

Post by Johnny555 »

xvector wrote: post #96
lstodd wrote: post #89

Earlier quoted context omitted.

And an unknown and unknowable attack surface. At least with the switch if the mic doesn't work you just check for magnets around it and that's it.

I'd argue the T2 chip is actually more secure than your method. Magnets can be removed. The T2 chip cannot. Not without rendering the computer unusable and the data irrecoverable. The chip provides a hardware disconnect for the microphone, just like your idea. Except it's baked into the silicon instead of an additional large part in the body of the computer. Regardless, if your attack model is "T2 chip is compromised…

I'd argue the T2 chip is actually more secure than your method. Magnets can be removed. The T2 chip cannot. Not without rendering the computer unusable and the data irrecoverable

If someone can physically modify your laptop, you've already been hacked, T2 chip or not.

if your attack model is "T2 chip is compromised"

I think the more realistic attack model is "Apple enables the undocumented 'turn on mic while closed' feature that it was required to add through a national security letter that they can't talk about."

And then that secret hack is either discovered (or stolen) by other government.

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#122

Post by Johnny555 »

sjwright wrote: post #66
JumpCrisscross wrote: post #22

Earlier quoted context omitted.

> the lid could control the switch Doing it on a chip sounds more reliable than adding a moving part.

And sounds more scalable too, if they wanted to start applying the same principle to other components like accelerometers, light sensors etc. The point (it seems) of the T2 chip is that it's isolated from the main system and has far fewer opportunities for exploitation, while leveraging efforts already expended for the iPhone. In my mind the eventual goal of the T1 / T2 etc chip line will be to do everything for a Ma…

And sounds more scalable too, if they wanted to start applying the same principle to other components like accelerometers, light sensors etc.

Is it easier the "turn off" signal from the T2 chip to each device to be turned off than it is to route the "turn off" signal from the lid closed switch/sensor to each device. Why does it have to pass through the T2 chip first?

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#123

Post by PascLeRasc »

justapassenger wrote: post #119
klodolph wrote: post #112

Earlier quoted context omitted.

Running on the same chip does not mean that there’s no isolation. The T2 has an ARM core with an MMU, different processes can be isolated from one another as well as you can on ordinary OSs. Given that you can’t load software on the T2 you’d have to find some remote hole and then do local privilege escalation. And still certain things will be impossible, even if you control the software on the T2, because there is no…

Phew, that's a solid model! No software ever had both remote holes and local privilege escalation!

What do you want instead? You seem to be pushing for hardware isolation and when Apple goes and does that, putting encryption and a few other features on its own chip designed to be more secure than the CPU, that's not a good thing?

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#124

Post by newnewpdro »

justtopost wrote: post #107
newnewpdro wrote: post #83

Earlier quoted context omitted.

When the microphone is a passive connected to a multifunction IC there's no such power rail.

Most laptop mics are condenser electret mics which usually use a small dc current, although not always.

Not the last time I went down this road hardening a Thinkpad, see Step 6 at [1] (not my site). I haven't bothered with any smartphones yet, so I can't speak to what they tend to use for a mic. But if I carried one I'd definitely rip out all the voice coils and rely on a pair of headphones w/integrated mic for voice comms to mitigate potential for eavesdropping.

[1] https://blog.patternsinthevoid.net/replacing-a-thinkpad-x60-...

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#125

Post by klodolph »

justapassenger wrote: post #119
klodolph wrote: post #112

Earlier quoted context omitted.

Running on the same chip does not mean that there’s no isolation. The T2 has an ARM core with an MMU, different processes can be isolated from one another as well as you can on ordinary OSs. Given that you can’t load software on the T2 you’d have to find some remote hole and then do local privilege escalation. And still certain things will be impossible, even if you control the software on the T2, because there is no…

Phew, that's a solid model! No software ever had both remote holes and local privilege escalation!

Sarcasm aside, this is part of a strategy called “defense in depth”, the general idea is that no part of your system can be completely secure so you add different types of layers to your security just to make it more difficult for attackers.

Since the T2 does not need to run user software there are additional options available to make it more secure which are not available for ordinary CPUs. For example, you could completely prevent executable code from being loaded without resetting the chip.

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#126

Post by bunnycorn »

shawnz wrote: post #56
GuB-42 wrote: post #24

Earlier quoted context omitted.

There is already a lid closed sensor. Adding another mechanical switch is more expensive, adds another point of failure, takes space, may interfere with the aesthetics, etc... The T2 chip probably also acts as a controller for a lot of the builtin sensors, including the microphone and lid closed switch. As a result, adding a feature to turn off the microphone when the lid is closed becomes trivial. Basically just add…

Why have the control go through a sophisticated programmable chip and not just use a simple transistor/relay directly connected to the sensor?

Why should it go through yet another redundant mechanism.

Have you ever seen a MacBook from the last 10 years? There are no physical switches, it's an hall sensor that works with the magnets that keep the thing closed.

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#127

Post by TheAceOfHearts »

A bit tangential, but if you want to track when programs are recording audio or video you should try out OverSight [0]. Although, since it's just software it's possible it can be bypassed by direct attacks, and it can sometimes fail to detect which program is accessing the webcam or microphone. Even with those limitations I still think it's better than nothing.

Micro Snitch [1] is another alternative, although it's more limited in its functionality since it doesn't try to detect what program is accessing your webcam or microphone. It also costs $3.99, while OverSight is free.

[0] https://objective-see.com/products/oversight.html

[1] https://obdev.at/products/microsnitch/index.html

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#128

Post by bunnycorn »

craftyguy wrote: post #90
dpkonofa wrote: post #62

Earlier quoted context omitted.

Malware doesn't have access to the T2. Presumably, the T2 is configurable separately from the rest of the hardware or anything else the system would have access to.

Unless specifics about the implementation are public, it's safer to say "...until it (malware) does have access to the T2" in response to your comment.

The Secure Enclave has been around since the 2013 and never was infected with malware and it was not for the lack of trying.

Re: Apple's T2 chip will prevent hackers from eavesdropping on your microphone

#130

Post by bunnycorn »

quickthrower2 wrote: post #102
ctdonath wrote: post #65

Earlier quoted context omitted.

My company (major telecom) literally gives away camera covers. Surely they'd do same for mics if there was a convenient cheap way. There's plenty of rumors about mics & cameras being commandeered by hackers & secret agencies. Apple gets ahead by actually securing mic access. Lots of people want it.

Rip the mic out Plug in USB mic when you need one.

Sure thing...

Tell that to toushands of employees of fortune 500, that don't care one bit about security, as it's not their responsabilty.

They will plug the USB mic and that would be it.

It even goes in the bag with the ports plugged in if it has space.

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