acoustic-keylogger VS tpm.dev.tutorials

You don't even need to attach it, other placements are sufficient as well. <https://github.com/shoyo/acoustic-keylogger/tree/master/acou...>

It's worse than that. Physical access to target hardware in any state for any length of time can result in full compromise in the future.

Brief access to target's premises can result in full compromise without even using a camera:

https://github.com/shoyo/acoustic-keylogger

On the hardware side, we've had enough advances in machine learning that acoustic "keyloggers" that can reconstruct a series of keystrokes based on an audio recording are starting to become viable: https://github.com/shoyo/acoustic-keylogger

>> The discrete TPM's threat model was never designed to cover you from attackers using oscilloscope to probe your laptop's SPI bus during the boot process for unencrypted data.

This is not really true. All TPMs (or at least since v2.0, but no matter if discrete or not) support encrypted session against passive eavesdroppers. There is also the possibility to protect against MiTM attacks, but that is more complex (since you then need to setup credentials).

See here [0]:

"Encryption sessions are useful for when the path to a TPM is not trused, such as when a TPM is a remote TPM, or when otherwise the path to the TPM is not trusted."

The issue is that the OS / Bootloader does not implement such mechanism.

[0] https://github.com/tpm2dev/tpm.dev.tutorials/blob/master/Int...

> A dTPM uses an unencrypted protocol to communicate with the CPU

While that is strictly speaking true, the TPM command set allows you to set up an encrypted session to the TPM using an ECDH or RSA key for key exchange that authenticates the TPM.

The problem is that the BMCs and BIOSes out there don't record a public key for a primary key on the TPM and then don't bother using encrypted sessions (not even opportunistically getting that public key from the TPM, which would defeat passive attacks).

That's a software problem, not a TPM problem!

I know that TPM 2.0 is a huge topic, so it's quite forgivable that people don't know these things. I've written a tutorial that might help: https://github.com/tpm2dev/tpm.dev.tutorials/tree/master/Int...

https://github.com/tpm2dev/tpm.dev.tutorials/tree/master/Int...

I have learned a fair bit since I wrote it, so I should probably edit it.