Implement Key replacement package for Image signing Key ECCKEY1

[Grogu]

The SBSFU framework allows users to employ multiple image signing keys, ECCKEY1, ECCKEY2, and ECCKEY3.

Is there a method to blacklist ECCKEY1 and replace it with ECCKEY4, which may be transmitted via a key replacement update package if the private key for ECCKEY1 is leaked/compromised?

Keys are compiled into code and stored in the SE Key region ROM, which is secured by MPU-RX + WRP + PCROP.

Please advise what options I have to replace the key which is compromised?

Assuming bootloader enhanced to differentiate between .sfb and key replacement package.

[Jocelyn RICARD · Accepted solution]

Hello @Community member​ 

There is no mechanism to implement such behaviour.

Robustness of SBSFU is relying on the immutability of the code and public key.

So, I have no solution to propose here.

Best regards

Jocelyn

[Grogu]

Thanks @Jocelyn RICARD​