It is possible to use sslget to submit information securely to Certificate System subsystems. For example, to submit a certificate request through a certificate profile enrollment for to a CA, the command is as follows:

sslget -e
"profileId=caInternalAuthServerCert&cert_request_type=pkcs10
&requestor_name=TPS-server.example.com-7889
&cert_request=MIIBGTCBxAIBADBfMSgwJgYDVQQKEx8yMDA2MTEwNngxMi
BTZmJheSBSZWRoYXQgRG9tYWluMRIwEAYDVQQLEwlyaHBraS10cHMxHzAdBgNVBA
MTFndhdGVyLnNmYmF5LnJlZGhhdC5jb20wXDANBgkqhkiG9w0BAQEFAANLADBIAk
EAsMcYjKD2cDJOeKjhuAiyaC0YVh8hUzfcrf7ZJlVyROQx1pQrHiHmBQbcCdQxNz
YK7rxWiR62BPDR4dHtQzj8RwIDAQABoAAwDQYJKoZIhvcNAQEEBQADQQAKpuTYGP
%2BI1k50tjn6enPV6j%2B2lFFjrYNwlYWBe4qYhm3WoA0tIuplNLpzP0vw6ttIMZ
kpE8rcfAeMG10doUpp
&xmlOutput=true&sessionID=-4771521138734965265
&auth_hostname=server.example.com&auth_port=9443"
 -d "/var/lib/rhpki-tps/alias" -p "password123" -v -n "Server-Cert cert-rhpki-tps"
 -r "/ca/ee/ca/profileSubmit" server.example.com:9443