Security Basics mailing list archives
Re: Hard disk Encryption
From: Alexander Klimov <alserkli () inbox ru>
Date: Sun, 22 Apr 2007 12:56:24 +0300 (IDT)
On Thu, 19 Apr 2007, Ali, Saqib wrote:
a TPM identifies a machine
TPM has a goal not only to identify a machine, but also to identify software that is currently executed by the machine. An attacker cannot unseal data if they do not have access to the TPM that sealed it; but if an attacker has the TPM and hardware tools, they can lie to TPM about the current state of the CPU and unseal the data.
For a reasonably secure system you need both user identification and machine identification.
Remember that we are discussing "hard disk encryption". How often an attacker gets a disk but does not get the only computer that can decrypt it? It is not the case for laptops, and even for portable storage it would be quite odd. That is in my opinion "machine identification" is almost useless for hard disk encryption.
I think we should close this discussion for right now, until an attack can be demonstrated on the TPM itself, rather then improper implementations of the technology.
The attack I described does not need to break "the TPM itself," it feeds TPM with false information (supposedly coming from the CPU) and asks it to unseal data. -- Regards, ASK
Current thread:
- Re: Re: Hard disk Encryption Balaji Prasad (Apr 12)
- Re: Re: Hard disk Encryption Ali, Saqib (Apr 12)
- Re: Re: Hard disk Encryption Alexander Klimov (Apr 15)
- Re: Re: Hard disk Encryption Ali, Saqib (Apr 16)
- Re: Hard disk Encryption Alexander Klimov (Apr 16)
- Re: Hard disk Encryption Ali, Saqib (Apr 16)
- Re: Hard disk Encryption Alexander Klimov (Apr 17)
- Re: Hard disk Encryption Ali, Saqib (Apr 17)
- Re: Hard disk Encryption Alexander Klimov (Apr 18)
- Re: Hard disk Encryption Ali, Saqib (Apr 19)
- Re: Hard disk Encryption Alexander Klimov (Apr 24)
- Re: Re: Hard disk Encryption Ali, Saqib (Apr 16)