3 ms·
fTPMs are invulnerable to interposing attacks, but if you add a second TPM and program it as Windows (eg) would and redirect all remote attestation requests to
by mjg59 3y ago
fTPMs are invulnerable to interposing attacks, but if you add a second TPM and program it as Windows (eg) would and redirect all remote attestation requests to that, the remote site has no way to know that this has happened.
- Nextgrid 3y agoMy understanding is that TPMs have vendor-embedded certificates/keys, so I guess eventually all discrete TPMs' keys will no longer be accepted by remotely-attestable services to protect against this attack - fTPM will be the only way. This is all theory though - workable TPM-backed DRM would require so much vendor cooperation, secure programming and break legitimate use-cases that it won't happen any time soon on conventional hardware. It would be cheaper for the media industry to just sell streaming boxes or exclusively target more locked-down platforms (iOS, Android) than try to make it work on generic Windows PCs.
- Mindwipe 3y agoOr just use the existing hardware security features that don't let the OS see what's in the relevant video memory at all. But as you say, that's a much, much smaller attack surface than trying to validate the OS.