ERROR:

 TLS_ERROR: BIO read tls_read_plaintext error: error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed 

Solution: Fedora/Centos

sudo nano /etc/environment

add the following two lines

NSS_HASH_ALG_SUPPORT=+MD5 
OPENSSL_ENABLE_MD5_VERIFY=1

Save the file, Logout from the system and log back in again.

CENTOS  Network Manager

edit: /usr/lib/systemd/system/NetworkManager.service

in [service] stanza add:

Environment="OPENSSL_ENABLE_MD5_VERIFY=1 NSS_HASH_ALG_SUPPORT=+MD5"

then execute commands:

systemctl daemon-reload
systemctl restart NetworkManager.service