Imagine having a device that has a TPM (Trusted Platform Module). This TPM is used to store keys. Some of these keys are sealed to PCR constraints, meaning that they can only be opened if the PCRs have certain values, i.e. the values they had when the key was created on the TPM. So far so good, works.
This device allows for software updates over USB. It is possible that these software updates contain a completely new BIOS, kernel, OS, etc., meaning that the PCR values inside the TPM would differ with update of the software components. The problem now is that I cannot use the sealed key anymore as the PCR values do not correspond to the expected ones. Is there any way to save the sealed key somehow and seal it to the new device software?