<Thread> Hi @ARCHOS
! Let's discuss a backdoor found in the EngineerMode app on the @ARCHOS 40 Power phonepic.twitter.com/RY5Yxw02zL
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There 2 possibilities:
- Set this flag will root the device
- This flag is set after a root procedure
As my device is not rooted, I cannot test it for now.
Anyway, it's clearly shows that a root procedure had been implemented by @ARCHOS without the knowledge of the user
You shouldn't call it a backdoor if you haven't tested that. Plus if it already needs root to write to /data, then so what? That process already has root so what would be the importance of this?
A root procedure implemented by the phone maker without the knowledge of the user is a backdoor...
Not sure you really understand the thing here. As said in the tweet this is a partial result but it clearly shows that @ARCHOS has a way to root the device.
The main hypothesis here is that this flag is set by another @ARCHOS system app. I will continue to dig to find how to trigger this procedure
Time to say a prayer for all those all-winner devices running that "rootmydevice" piece of code : https://github.com/allwinner-zh/linux-3.4-sunxi/commit/e8bb679bbb18b90174381bea0e643eb81a92030b … 
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