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The fact that the mike defaults to on after power on is completely understandable from a user interface perspective, but from a security perspective it makes th

The fact that the mike defaults to on after power on is completely understandable from a user interface perspective, but from a security perspective it makes the mute switch useless. Why? Because any attacker that has penetrated far enough to be able to control the SOC in order to snoop can also trigger a SOC reset in order to make sure that the mike is enabled before they start snooping. A physical switch would have been a better choice, if it was actually for security instead of security theatre.

dvfjsdhgfv 6y ago
> The fact that the mike defaults to on after power on is completely understandable from a user interface perspective A compromise would be to play a message after turning the device on, requiring user to take action and unmute it or leave muted. This shouldn't be a problem in most scenarios as Echo is meant to be powered once and run for a long time, so it would be just a minor inconvenience.
- kylegordon 6y ago
  I'm curious as to what the state would be after a firmware upgrade?
- lemonspat 6y ago
  > would be to play a message after turning the device on It does this already
jstanley 6y ago
At least it sounds like the red light would go out in this case, so you'd have some indication that something is up.
- cyphar 6y ago
  That assumes you check whether the mute light is active on a fairly regular basis. If you just turn it off and don't check on it, the light is pretty much useless as an indicator.
  - lemonspat 6y ago
    The boot up sequence does an audible musical tone and says "Hello", so an attacker is not silently going to reboot it and listen in
    - cyphar 6y ago
      If you know everyone in the house is absent during working hours (a reasonable assumption) or that your target has children and they need to pick them up from school at a certain time, just reboot it during that window. Eventually they will forget to check that the microphone is still off when they get home (if they ever check in the first place).
rahimiali 6y ago
The R line for the flip flops goes to the SoC, but we don’t know if it’s tied to SoC’s reset line or if it’s a GPIO on the SoC. In the former case, you’d have to reset the SoC to turn on the mic. In the latter, you can just turn on the mic without reset. In either case, the LED always shows the true state of the mic.

dvfjsdhgfv 6y ago

> The fact that the mike defaults to on after power on is completely understandable from a user interface perspective A compromise would be to play a message after turning the device on, requiring user to take action and unmute it or leave muted. This shouldn't be a problem in most scenarios as Echo is meant to be powered once and run for a long time, so it would be just a minor inconvenience.

kylegordon 6y ago
I'm curious as to what the state would be after a firmware upgrade?
lemonspat 6y ago
> would be to play a message after turning the device on It does this already

jstanley 6y ago

At least it sounds like the red light would go out in this case, so you'd have some indication that something is up.

cyphar 6y ago
That assumes you check whether the mute light is active on a fairly regular basis. If you just turn it off and don't check on it, the light is pretty much useless as an indicator.
- lemonspat 6y ago
  The boot up sequence does an audible musical tone and says "Hello", so an attacker is not silently going to reboot it and listen in
  - cyphar 6y ago
    If you know everyone in the house is absent during working hours (a reasonable assumption) or that your target has children and they need to pick them up from school at a certain time, just reboot it during that window. Eventually they will forget to check that the microphone is still off when they get home (if they ever check in the first place).

rahimiali 6y ago

The R line for the flip flops goes to the SoC, but we don’t know if it’s tied to SoC’s reset line or if it’s a GPIO on the SoC. In the former case, you’d have to reset the SoC to turn on the mic. In the latter, you can just turn on the mic without reset. In either case, the LED always shows the true state of the mic.