Re: [Trans] Threat model outline, attack model

Stephen Kent <> Mon, 15 September 2014 19:03 UTC

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Date: Mon, 15 Sep 2014 14:52:52 -0400
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Subject: Re: [Trans] Threat model outline, attack model
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> Stephen,
> thank you for the formal description of treat model.
> But I think that the Auditors should be mentioned in it too. If I am 
> not mistaken, they are designed to watch the certificates with 
> suspicious properties (CA permissions, etc.).
> So the treats which are to be avoided using the Auditors seems to be 
> case, the CT mechanisms have detected mis-issuance, but are 
> not able to remedy the problem. (See Note 4 below.)

In 6962-bis (-04) the definition of the Auditor function is:

Auditors take partial information about a log as input and verify

that this information is consistent with other partial information

they have.

This is way too vague to be meaningful. So, I agree that an Auditor 
might be relevant
to the attack analysis, I didn't include it this time because there is 
not a sufficiently
detailed description of its functions. The examples of what an Auditor 
"can" do don't
mention checking cert content against a set of criteria. They focus on 
detecting log
inconsistencies. So, maybe Auditors should be mentioned in the 
discussion of detecting
log misbehavior.