What are Chained/Intermediate Certificates?

Chained certificates, also known as intermediate certificates, are extensions from your CA's trusted root certificate. An intermediate certificate is a subordinate certificate issued by the trusted root . The result is a certificate chain that begins at the trusted root CA, through the intermediate and ending with the SSL/TLS certificate issued to you. Such certificates are called chained root certificates.

Creating certificates directly from the CA root certificate increases the risk of root certificate compromise, and if the CA root certificate is compromised, the entire trust infrastructure built by the SSL provider will fail. The usage of intermediate certificates for issuing SSL certificates to end entities, therefore, provides an added level of security.