juurisertifikaatit

Juurisertifikaatit, also known as root certificates, are the foundation of the trust hierarchy in public key infrastructure (PKI). They are digital certificates issued by a trusted Certificate Authority (CA) that vouch for the authenticity of other certificates. In essence, a root certificate acts as the ultimate source of trust. When your web browser or operating system encounters a digital certificate for a website or service, it checks if that certificate was signed by a CA that it trusts. This trust is established because the browser or OS has a pre-installed list of trusted root certificates.

If the certificate presented was signed by a CA whose root certificate is in the system's trust store, the connection is considered secure. If not, a warning is typically displayed to the user, indicating a potential security risk. Root certificates are typically self-signed, meaning they certify themselves. This might seem circular, but the trust in a root certificate comes from its distribution through operating systems, web browsers, and other trusted software by reputable organizations.

The security of the entire PKI system relies heavily on the security of root certificates. If a root certificate is compromised, an attacker could potentially issue fraudulent certificates that would be trusted by systems that rely on that compromised root. Therefore, securing root certificate repositories and the processes for issuing them is of paramount importance. Certificate pinning is a technique used to further enhance security by explicitly specifying which certificates or CAs a client should trust for a particular service, reducing reliance solely on the general trust store.