[keisborg]

It it possible to create firmware that is encrypted and cannot be read out. Espressif state there is no security issues, but I have a feeling that these debug commands may be used to read out the flash of a properly secured esp32 that otherwise would not be possible…

[unsnap_biceps]

https://docs.espressif.com/projects/esp-idf/en/stable/esp32/... Doesn't say anything about reading the encrypted flash as being blocked, just that it will be the encrypted contents, same as if you pull the flash chip off and read it.

You need arbitrary code execution on the main cpu to execute the debug commands. Once you have that, it's game over anyway. Why not just post the data to a url rather than trying to smuggle it out in Bluetooth headers? Or just broadcast it via normal Bluetooth packets?

There's no issue here.

[keisborg]

I would hope so, but on

Tarlogics blog post, it is mentioned “modifying chips arbitrarily”, “infecting chips with malicious code”, “obtain confidential information stored on them”.

Even though they rephrased the backdoor wording, the remaining statements make me believe the undocumented functions can be used to gain code execution on the main cpu.

[red-iron-pine]

why do we believe their documentation, when they didn't list this in the first place?

they're either lying, or failed to disclose details previously.

why do you think they're doing a better job this time around? there may in fact be no serious threat, but now anything and everything is called into question.

[ajross]

> I have a feeling that

The problem is that Tarlogic went full nuclear with "There is a Backdoor in ESP32!!" all over the tech media based on logic that aligns with yours. "They had a feeling."

This is not a backdoor. It is arguably poor security design as one might like it if the BTLE controller was a separate permissions domain. But it isn't, and doesn't have to be, and there isn't even a theoretical vulnerability demonstrated.