macOS unable to open any non-Apple application

Unbelievable. When I read the tweet (tried to post here as well), I suddenly realized why my Mac was unresponsive an hour ago.

Here is another tweet that describes the problem in more detail:

https://mobile.twitter.com/llanga/status/1326989724704268289

> I am currently unable to work because macOS sends hashes of every opened executable to some server of theirs and when `trustd` and `syspolicyd` are unable to do so, the entire operating system grinds to a halt.

EDIT:

As others pointed out, I put this to my `/etc/hosts` file and refreshed it like so:

    sudo emacs /etc/hosts # add `0.0.0.0 ocsp.apple.com` 
    sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder # refresh hosts

Can apple not use security certificates to verify publishers ? why does it need to go to their servers ?

The URL mentioned in sibling comments suggests this has to do with certificate revocation (OCSP): https://en.wikipedia.org/wiki/Online_Certificate_Status_Prot...

I agree that breaking system availability when an OCSP server isn't available is user-hostile and unnecessary.

The alternative is OCSP being allowed if internet isn't available, which is a security risk for reasonable defense-in-depth strategies.