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Comment by Godel_unicode | Hacker News Reader

If only there were a way to revoke certificates. Like, some kind of list.

Revocation lists get huge, ultimately becoming another reason to limit cert lifetime (you don't have to tell people you revoked a certificate which is expired naturally).

Very few things check revocation, unfortunately - it puts an extra hop on the fast path of connecting to a server. OCSP stapling is pretty much the only thing a browser would care about - having the server fetch a signed OCSP response that is good for a limited period of time (say, hours), and send that along with the certificate during negotiation.

Or, you could just have the server fetch a certificate thats good for a limited period of time.

If only such a list were actually effective rather than the majority of clients not bothering to check it.

CRLs do not work in practice, and major clients routinely ignore them.

OCSP stapling together with OCSP Must Staple is the way to go here. All major browsers support these.

Firefox still does normal OCSP requests, Chromes does not. So if you are a Chrome user, to my understanding, there is now way to know if the server certificate was revoked or not, other than OCSP stapling together with OCSP Must Staple. Additionally, both Chrome and Firefox ship a list of revoked certificates, but it may not be updated quickly enough and as far as i can tell it mostly contains roots and intermediates.

Revocation requires the private key

This is not true. In Let's Encrypt/ACME for example, you can simply obtain authorizations for all the domains a certificate is valid for and request revocation [1]. The only thing you still need to revoke the certificate, is the certificate itself. The certificate can be obtained from CT logs.

[1] https://tools.ietf.org/html/rfc8555#section-7.6

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