Don't close your MacBook with a cover over the camera

Post by rovr138 » Fri, Jul 10, 2020, 10:11 PM UTC

aahhahahaaa wrote: post #255

the-pigeon wrote: post #196

Earlier quoted context omitted.

But can't you specifically wire the indicator light to always be lit if the camera has power? I don't see Apple claiming they've done that but a correct design would make the indicator light work that way and be related to software at all. Meaning you could only disable the indicator light by physically modifying the device.

This has been the case for quite some time (10 years or so). I've torn apart two Macbooks to specifically test this and the LED is enabled when the camera receives power. It's impossible to disable with software. You can modify the Macbook of course, which is why the paranoid type will still use tape. Some attacks I've seen will take a photo with the camera as fast as possible so you might not notice, but the light w…

Post by mthoms » Fri, Jul 10, 2020, 10:11 PM UTC

dasudasu wrote: post #248

axoltl wrote: post #169

Earlier quoted context omitted.

Hi! I was the security architect for this feature on recent Macs. The LED is wired to the camera PMIC and is powered by the voltage rail that powers the camera. The PMIC will always remain on if the system has power. Macs newer than 4 or so years also have a feature that forces the LED to stay lit for at least 3 seconds after it has been turned on to prevent the single-frame-grab attack.

So you have to perpetually watch out for the LED indicator to see if it ever randomly turns on for 3 seconds? And what if it does come up unexpectedly? At this point it's too late and you've already been captured. A mechanical cover that can slide on and off the camera seems like much better security.

Post by eecc » Fri, Jul 10, 2020, 10:12 PM UTC

alunchbox wrote: post #185

NovemberWhiskey wrote: post #54

Earlier quoted context omitted.

>2013: iSeeYou: Disabling the MacBook Webcam Indicator LED https://jscholarship.library.jhu.edu/handle/1774.2/36569 ... applies only to older Mac notebooks from like 2008 period which are long since obsolete according to Apple's announced support policy. >2016: Your Mac’s Camera Can Be Hacked https://www.intego.com/mac-security-blog/your-macs-camera-ca... . ... refers specifically the exploit above. >2016: Former NSA…

There's a reason Zukerberg's laptop has its mic and camera tapped up. It doesn't matter what device you use unless there's a physical switch to disconnect it'll never be safe. Software can ALWAYS have zero days, just because it hasn't been exploited yet doesn't mean it can't be.

Post by inopinatus » Fri, Jul 10, 2020, 10:13 PM UTC

foota wrote: post #223

ohazi wrote: post #202

Earlier quoted context omitted.

This is the only correct design, yet almost nobody does this. One of the challenges is verifying that this was done correctly. You may be able to verify a design like this once with a teardown, but it's impractical to verify your particular device, and next to impossible to re-verify this every time you leave your laptop unattended.

My threat model doesn't involve someone disassembling my laptop and rewiring it, at that point they might as well just plant a bug.

Post by valuearb » Fri, Jul 10, 2020, 10:13 PM UTC

SAI_Peregrinus wrote: post #135

GuiA wrote: post #89

Earlier quoted context omitted.

I had a laptop with a physical switch for WiFi/Bluetooth in 2006 or so (with a matching orange/blue light that would turn up when you toggled it). The problem was that this was actually all done by a software driver - when I booted into Linux with the laptop I was surprised to find that the bluetooth/wifi modules were on regardless of the switch's position. At the end of the day, unless you have a really nice microsc…

I have a Lenovo Thinkpad T480. Its webcam switch is a slider that covers the webcam lens. You don't need a fancy microscope, or a solid understanding of EE, or tens of thousands of hours. You need the ability to see the slider cover the lens. Takes all of half a second and at least 1 eye.