Re: [Acme] dns challenges and dynamic dns services (security considerations for domain holders)

moparisthebest <admin@moparisthebest.com> Fri, 29 January 2016 15:11 UTC

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Subject: Re: [Acme] dns challenges and dynamic dns services (security considerations for domain holders)
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Hello Frederik,

On 01/29/2016 08:47 AM, Frederik Braun wrote:
> I'm concerned that an attacker might request
> _acme-challenge.dyndns.example and get a valid certificate for
> dyndns.example.

Does there exist a dynamic DNS service that allows setting TXT records?
 I've never seen one.  Also this can also be easily mitigated by them
just disallowing the _acme-challenge subdomain similar to the way they
probably all disallow www.

Thanks,
moparisthebest