I just had a similar problem with Error#77 on CentOS7. I was missing the softlink /etc/pki/tls/certs/ca-bundle.crt that is installed with the ca-certificates RPM.
‘curl’ was attempting to open this path to get the Certificate Authorities.
I discovered with:
strace curl https://example.com
and saw clearly that the open failed on that link.
My fix was:
yum reinstall ca-certificates
That should setup everything again. If you have private CAs for Corporate or self-signed use make sure they are in /etc/pki/ca-trust/source/anchors so that they are re-added.