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Re: [Acme] Content-Type and file extensions for HTTP01 challenges

Peter Eckersley <pde@eff.org> Fri, 13 November 2015 01:12 UTC

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Date: Thu, 12 Nov 2015 17:12:59 -0800
From: Peter Eckersley <pde@eff.org>
To: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [Acme] Content-Type and file extensions for HTTP01 challenges
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I should have added another option, 3b, drop the Content-Type
restriction but allow file extensions.

Sounds like that would be a win on IIS.

On Thu, Nov 12, 2015 at 05:05:53PM -0800, Martin Thomson wrote:
> On 12 November 2015 at 16:44, Peter Eckersley <pde@eff.org> wrote:
> > But is 3 the best answer?
> 
> Of those presented, I think so.  I know that this isn't a great answer
> (it's bad already, so bad must be OK), but being able to drop things
> into .well-known opens a raft of other interesting attacks.
> 
> More seriously, I think that the other options all have deployment
> complications that far outweigh the marginal benefit that extra
> checking might provide.
> 
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-- 
Peter Eckersley                            pde@eff.org
Chief Computer Scientist          Tel  +1 415 436 9333 x131
Electronic Frontier Foundation    Fax  +1 415 436 9993

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