Certificates are designed to link a public cryptographic key to a person, IT system, or organisation. This link with the key is then protected cryptographically using a digital signature, which usually comes from a trustworthy neutral organisation.

These certificates are then used by third parties to verify digital signatures of the person, IT system, or organisation identified in the certificate. Alternatively, the key stored in the certificate can be used for an asymmetric encryption procedure to encrypt communication with the certificate holder.

If a certificate like this is forged, the digital signatures may be falsely verified as correct and associated with the person, IT system, or organisation in the certificate. Furthermore, data may be encrypted and sent with a key that is potentially insecure.