Conversation

Emily Stark
@estark37
a small human has been consuming all my blogging time lately, but I decided to get back into the game with a post full of terrible ideas for how to abuse Certificate Transparency to re-create public key pinning:
emilymstark.com
Certificate Transparency is really not a replacement for key pinning
I’ve noticed that there’s a common misconception that Certificate Transparency is a replacement for HTTP public key pinning. If those words make no sense to you: HTTP public key pinning was a...
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Aranjedeath
@Aranjedeath
Replying to
@estark37
and
@Cryptoki
Wondering if browser could enforce CAA list if DNS was delivered securely lol 95% of the benefits with 95% less pain over HPKP. Does not solve "My CA was breached", but helps with other CA breached/etc
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Daniel Micay
@DanielMicay
Replying to
@Aranjedeath
@estark37
and
@Cryptoki
This is provided by TLSA records, not CAA. TLSA records work well. You can use them to pin the hash of a leaf key, an intermediate key or a root key. You can have multiple valid pins which allows rotation, etc. You can set TTL low to minimize disruption from making mistakes.
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Daniel Micay
@DanielMicay
Replying to
@DanielMicay
@Aranjedeath
and 2 others
TLSA records (DANE) are already widely used for email, and Microsoft is adopting them for Outlook. Google is adopting a much weaker, inherently insecure approach (MTA-STS) for Gmail which works like solely using http URLs with HTTPS redirects + dynamic HSTS, no preloading, no CT.
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