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Bypassing disk encryption on systems with automatic TPM2 unlock

(oddlama.org)
189 points arjvik | 2 comments | 17 Jan 25 03:00 UTC | HN request time: 0s | source
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acheong08 ◴[17 Jan 25 04:12 UTC] No.42733994[source]▶
I don't understand why anyone would use passwordless disk encryption. It just seems inherently vulnerable, especially with the threat model of physical compromise.

Entering a password on boot isn't even that much work

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dangero ◴[17 Jan 25 04:43 UTC] No.42734171[source]▶
Depends on the use case. If boot requires a password, the computer can never lose power or be rebooted without human presence. That’s not always practical.
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1. prmoustache ◴[17 Jan 25 09:29 UTC] No.42735690[source]▶
That is what remote kvm are for and if you do that on commodity hardware you can start a tiny ssh server starting up from an initrd. Having said that an attacker with local access could change the initrd without your knowledge so that it logs the password you enter so it is not necessarily the most secure solution.
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2. deno ◴[17 Jan 25 11:40 UTC] No.42736516[source]▶
You’ve answered it yourself. Without TPM you have no idea if you can provide the secret to the system or if it’s compromised. Whether that secret comes from TPM or network is secondary.