Re: [therightkey] DNSNMC deprecates Certificate Authorities and fixes HTTPS security

Rob Stradling <rob.stradling@comodo.com> Fri, 03 January 2014 15:28 UTC

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Date: Fri, 03 Jan 2014 15:28:11 +0000
From: Rob Stradling <rob.stradling@comodo.com>
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To: Leif Johansson <leifj@mnt.se>, therightkey@ietf.org
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Subject: Re: [therightkey] DNSNMC deprecates Certificate Authorities and fixes HTTPS security
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On 03/01/14 14:29, Leif Johansson wrote:
> On 2014-01-03 14:24, Ralph Holz wrote:
>> Hi,
>>
>>> My understanding of what Jakob wrote is that he holds the key for a
>>> subordinate CA. Unless the CA that "signed" that subordinate has
>>> been removed from trust lists then that subordinate would still be
>>> useful, yes.
>> The subordinate certificate is blacklisted in browsers. Furthermore,
>> Mozilla does not accept any non-root certs with MD5 signatures since
>> mid-2011.
>>
>> Ralph
>
> Assumes you run an updated browser, right?

Yes.

There's only so much we can do to protect folks who don't update their 
browsers.  It seems very unlikely that MD5 signatures are the biggest 
threat that they face.

> Blacklisting isn't part of the PKIX trust model, but a band-aid used to
> fix the lack of deployed/able revocation.

So?

-- 
Rob Stradling
Senior Research & Development Scientist
COMODO - Creating Trust Online