Re: [Acme] ACME vulnerabilities in SimpleHTTP due to common webservers' default virtual host semantics

Jakub Warmuz <jakub.warmuz@gmail.com> Sat, 09 January 2016 14:00 UTC

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From: Jakub Warmuz <jakub.warmuz@gmail.com>
Date: Sat, 09 Jan 2016 13:59:44 +0000
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To: Peter Wu <peter@lekensteyn.nl>
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Cc: Peter Eckersley <pde@eff.org>, Niklas Keller <me@kelunik.com>, IETF ACME <acme@ietf.org>
Subject: Re: [Acme] ACME vulnerabilities in SimpleHTTP due to common webservers' default virtual host semantics
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On 8 January 2016 at 23:56, Peter Wu <peter@lekensteyn.nl> wrote:
> It cannot be
> delegated via proxying because the server needs to parse the Client
> Hello first.


You could run a load balancer that proxies all requests to
*.acme.invalid to a Let's Encrypt client. There is (quite old)
tutorial on how to achieve that with HAProxy at
https://coolaj86.com/articles/lets-encrypt-with-haproxy/.

-- 
Yours virtually,
Jakub Warmuz