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Comment by NavinF

21 hours ago

>I had Claude write a tool to patch out the table entry for camera activity, fix up the integrity hash, and flash it to the camera. A quick test showed that the green LED that normally illuminates while recording no longer turned on. Horrifying!

Oof. Apple claims this is not possible for macbook cameras because the LED can't be controlled from software. Wish more manufacturers would do the same.

> the LED can't be controlled from software

If you look at tear downs apparently it is connected to the webcam so it is energized when the webcam receives power making it nearly impossible to defeat.

You can say a lot about Apple but the engineering is clever at the hardware level.

  • It's not even that clever, really. The camera power rail must be physically close to the camera, so it's trivial to hang an LED off it. A device manufacturer has to go out of their way to make it so the LED and camera function are independent, and I'm sure many do, for the worst reasons you can possibly think of.

    • It could be a typical design that the camera and LED always have power, and the LED is switchable.

      Giving the camera plus LED a separate power supply means that the camera has to boot or come online, which maybe increases the dwell time. And the camera is not visible on the USB bus when powered off.

      I think there's more engineering to Apple's design than it first seems.

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  • This still would allow one to "strobe" the power line making it impossible for a human to see the LED but the camera could still capture snapshots and at a decent framerate even.

    • Naw the LED stays on a little longer after you stop capturing image data. They either have burned in firmware or a simple circuit (RC and comparator) that stops your attack.

One of my old Logitech webcams have its recording light wired up to V4L2 protocol directly. I can change its recording light mode (on/off/blink) from software by changing recording light mode directly. Wonder whether that Insta360 also had that.

I'd have tried that first before diving into the firmware head-first.

Apple also claims that iMessage is end to end encrypted. Their privacy stance is 99% posturing.

  • The teardown showed this is the 1% right?

    Also I thought you could trust iMessage if, unlike everyone, you disabled iCloud backup (and, unlike everyone, so did the recipient). Perhaps a way for the feds to be able to pin dumb criminals while giving investigative journalists & dissidents a way to stay safer.

    • Even with "E2E" encryption with iMessage, you're still trusting Apple completely and totally with key distribution. If a new device is added to your account by an attacker or by Apple themselves, your existing devices will happily loop them in to share iMessage access with them. The vast, vast majority of iMessage users are never going to dig into the Apple keychain app to actually check what keys are being trusted and this is something that can be targeted to a single account so no one outside of Apple never even needs to know it happened.

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