Re: [Acme] tls-sni-01 validation compromise

Thomas Lußnig <lussnig@suche.org> Fri, 22 January 2016 20:30 UTC

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Subject: Re: [Acme] tls-sni-01 validation compromise
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Hi,

these problem is not new. I raised the roblem with letsencrypt over an 
month ago.
Better Would be:
Client Send clientnone,ECDSA-SHA256(servernonce,clientnonce)

The cert for <fqdn>.challenge.amce contain the public key.
So the client had proved he control the server