kaputnikGo / PilferShushJammer

Light Android AOSP application to test microphone jamming techniques to combat Cross-Device Tracking (XDT)
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The phone’s built-in voice recorder and camera can still use the microphone #27

Closed 11fen closed 4 years ago

11fen commented 4 years ago

The phone’s built-in voice recorder and camera can still use the microphone Android version: 10 Phone model: Redmi 10x 4g miui12

kaputnikGo commented 4 years ago

if they are installed as "system apps" with elevated privileges then they will always be able to run. will look into this, but i suspect its something to do with the additional APIs that miui adds to its version of android.
thanks for the report.

kaputnikGo commented 4 years ago

MIUI 12 MiuiCamera.apk limited scope xml trawling reveals:

System apps/Camera/Settings

which means that camera is a system app and as such will always override user apps, including PilferShush Jammer

11fen commented 4 years ago

Is it reasonable for audio recorders and cameras to obtain such high permissions?

Can the voice recorder prohibit calling the microphone?

kaputnikGo commented 4 years ago

on android its by design that system apps have greater priority. for instance you are using some sound recording app downloaded off google play and a phone call comes in, the phone app takes over control of the microphone and stops the recording app from hearing anything. this is a privacy regulation thing in some countries too. So for a basic android phone it will have a camera app as part of it operating system. in the MIUI case they have added their own MIUI apps to the system ones. if the voice recorder is a MIUI app then it also probably has system privileges.

You may be able to deny access to the microphone from a MIUI app in the system settings and permissions manager area (App info -> Permissions). But this probably doesn't help you much.