[Cryptography] distrusted root CA: WoSign

[Ben Laurie]

On 2 October 2016 at 20:41, Florian Weimer <fw at deneb.enyo.de> wrote:
> * Georgi Guninski:
>
>> Don't get "distrust future certs". Mozilla either trust root(s) or not.
>> Root(s) can trivially sign "old" cert requests, requiring old date now.
>> Having in mind the chinese have the Startcom, roots, they can issue
>> essentially whatever chaining up to root as long as the roots are trusted.
>
> The idea is to whitelist certificates which have been logged to the
> Certificate Transparency servers prior to a cut-off date.  As long as
> you trust the timestamps of those servers (or even just your previous
> downloads you have kept), the CAs cannot backdate that.

Whitelisting is, of course, technically possible, but its _big_. Even
the whitelist for EV certificates was close to what Chrome would
tolerate - I doubt there will actually be a whitelist, just
monitoring.