[mananaysiempre]

Is OCSP stapling somehow defective? Aside from being mostly unimplemented on the client side. It does limit revocation latency to two days or so, but that’s probably as short as it’s can realistically be without CAs seriously getting into high availability.

[lapcat]

I don't think you understand the context here. These are not web certificates, they're code signing certificates. There's only one CA in this case, and that's Apple, who issues Developer ID certificates to registered Mac developers to sign their apps, which are then distributed to users and installed on their Macs. Whenever an installed app is launched, macOS checks whether the code signing certificate has been revoked by Apple. So OCSP stapling is effectively irrelevant here.

[musicale]

Thanks for the excellent response.

Yeah, even if a time-limited OCSP validation cert is stapled to the app download (which seems like it would be easy to do on the Mac App Store at least), that doesn't seem to meet Apple's apparent desire for fast revocation based on online validation. (Or perhaps for user and app "analytics", but let's assume they are motivated by security and care about privacy.)

As a user I think I might be fine with something like cert stapling for App Store apps, and a cert blacklist for everything else.

On a possibly unrelated note, it is astonishing how long it takes Xcode to validate/install/start up the first time. I thought it was simply hung but it finished in a few hours.