Mitigation for APPPROTECT attack?

RE: Mitigation for APPPROTECT attack?

Vincent Belaïche — Tue, 04 Feb 2025 13:50:37 GMT

Thank you for your reply, it is crystal clear.

RE: Mitigation for APPPROTECT attack?

Jørgen Holmefjord — Tue, 04 Feb 2025 13:44:35 GMT

[quote] but if the bootloader is based on SDK 15.x.x, the SystemInit of the bootloader will not call nrf52_handle_approtect(), it will be called only when the SystemInit of the App is called, but then you have had some sort of SoftReset when the bootloader starts the App, so you are not directly after a hard reset. Does it matter ?[/quote]

Correct, the full protection will not be enabled until the application code runs, meaning that the bootloader is not protected.

[quote]One more question : does it mean that during the execution of the bootloader the attack mitigation is not done,so there is still some time gap in which the attack would be possible (said otherwise upgrading the bootloader to SDK 17.1.0 would be advisable).[/quote]

Yes, upgrading the bootloader to SDK17.1.0 or the required MDK version is definitely advisable.

RE: Mitigation for APPPROTECT attack?

Vincent Belaïche — Tue, 29 Oct 2024 10:06:03 GMT

Dear Jørgen Holmefjord ,

I have a similar question concerning the AppProtect attack mitigation as described by In 141 v1.1. If I use SDK 17.1.0 for the Application but the booloader is not upgraded and is still based on SDK 15.x.x, will my product benefit from the mitigation. The international notice says « 4. Perform a hard reset to protect the device. The programmed code from step 2 will write APPROTECT.FORCEPROTECT to Force (0x00). », but if the bootloader is based on SDK 15.x.x, the SystemInit of the bootloader will not call nrf52_handle_approtect(), it will be called only when the SystemInit of the App is called, but then you have had some sort of SoftReset when the bootloader starts the App, so you are not directly after a hard reset. Does it matter ?

One more question : does it mean that during the execution of the bootloader the attack mitigation is not done,so there is still some time gap in which the attack would be possible (said otherwise upgrading the bootloader to SDK 17.1.0 would be advisable).

RE: Mitigation for APPPROTECT attack?

Jørgen Holmefjord — Mon, 29 Jun 2020 13:26:56 GMT

Hi,

The available information can be found in IN133 Informational Notice v1.0. For questions about roadmaps and future plans, please contact your regional sales manager.

If you do not have the contact details, please send me a private message with your location and I will provide you with the information.

Best regards,
Jørgen