> TPM+PIN should actually mean the TPM itself cannot release the keys
It does release the (wrapped) key actually (the above cyberlabs link explains it), it's just that the KP data this time has additional layers of encryption that are based on the PIN, which is decrypted in software after the fact. This means you can crack it offline. With the default minimum of 6 digits you can probably bruteforce it within a day.
If you're paranoid I might suggest switching to a full password-based pre-boot auth option instead of the PIN.
Or if you have physical access, you can probe the TPM chip with a SPI decoder to get the key directly: https://post-cyberlabs.github.io/Offensive-security-publicat...
Another method is via PXE (still not patched on most systems apparently): https://github.com/andigandhi/bitpixie
> TPM+PIN should actually mean the TPM itself cannot release the keys
It does release the (wrapped) key actually (the above cyberlabs link explains it), it's just that the KP data this time has additional layers of encryption that are based on the PIN, which is decrypted in software after the fact. This means you can crack it offline. With the default minimum of 6 digits you can probably bruteforce it within a day.
If you're paranoid I might suggest switching to a full password-based pre-boot auth option instead of the PIN.