SSL_connect returned=1 errno=0 state=error: certificate verify failed

Try setting SSL’s environment variables to the proper location for your distro, e.g.

CentOS/RHEL:

export SSL_CERT_DIR=/etc/pki/tls/certs
export SSL_CERT_FILE=/etc/pki/tls/cert.pem

Ubuntu/Debian:

export SSL_CERT_DIR=/etc/ssl/certs
export SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt

This worked for me.