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Andrew Ayer


Duplicate Signature Key Selection Attack in Let's Encrypt

Comment by Andrew Ayer

Posted in reply to Comment by Reader Eivind.

This comment is owned by whoever posted it. I am not responsible for it in any way.

More powerful attackers can certainly respond with fake DNS replies and obtain certificates for any domain they like. This is a flaw inherent to all domain validation (DV) certificates. The solution is a combination of certificate transparency and public key pinning so that misissued certificates can detected and blocked.

But this blog post was about an attack which anyone on the Internet could have conducted, not just NSA-level adversaries.

| Posted on 2015-12-04 at 15:49:37 UTC by Andrew Ayer | Parent | Reply to This

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