Skip to Content [alt-c]

Andrew Ayer

Sections

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

Post a Reply

Your comment will be public. If you would like to contact me privately, please email me. Please keep your comment on-topic, polite, and comprehensible. Use the "Preview" button to make sure your comment is properly formatted. Name and email address are optional. If you specify an email address it will be kept confidential.

Post Comment


(Optional; will be published)


(Optional; will not be published)


(Optional; will be published)


  • Blank lines separate paragraphs.
  • Lines starting with ">" are indented as block quotes.
  • Lines starting with two spaces are reproduced verbatim.
  • Text surrounded by *asterisks* is italicized.
  • Text surrounded by `back ticks` is monospaced.
  • URLs are turned into links.