Cybersecurity 101back-iconWhat is a Certificate Signing Request (CSR)?

What is a Certificate Signing Request (CSR)?

A Certificate Signing Request (CSR) is a digitally signed request generated by an entity when requesting a digital certificate from a Certificate Authority (CA). It contains information that helps the CA identify the requester and includes the public key that the CA will associate with the certificate it issues.

A CSR is an essential part of Public Key Infrastructure (PKI). It enables Certificate Authorities to validate certificate requests before issuing digital certificates used for authentication, encryption, and secure communications.

Why is a Certificate Signing Request important?

A CSR provides the information a Certificate Authority needs to issue a digital certificate. Rather than creating the certificate directly, the requester first generates a public-private key pair and then creates a CSR containing the public key and identifying information.

In a secure CSR workflow, the private key should remain with the requesting system, helping protect the key material associated with the certificate. Once the CA validates the request, it issues a certificate that the entity can install alongside the corresponding private key.

What information does a CSR contain?

A Certificate Signing Request includes several fields that help identify the requester and associate the request with a public key.

CSR Component  Purpose 
Public key  Becomes part of the issued digital certificate 
Common Name (CN)  Identifies the domain, device, or service requesting the certificate 
Organization details  Provides organizational identity when applicable 
Country and locality  Identifies the requester’s location information 
Digital signature  Verifies that the request was signed using the private key corresponding to the included public key 

The exact information required depends on the certificate type and the validation process used by the Certificate Authority.

How does a Certificate Signing Request work?

The CSR process is a standard step in obtaining a digital certificate.

Step  Description 
Key pair generation  The requester creates a public and private key pair. 
CSR creation  A CSR is generated using the public key and identity information. 
Submission  The CSR is submitted to a Certificate Authority. 
Validation  The CA verifies the information based on the certificate type. 
Certificate issuance  The CA signs and issues the digital certificate. 
Installation  The issued certificate is installed with the matching private key. 

Because the certificate links to the original key pair, organizations must protect the private key throughout the process.

CSR vs. Digital Certificate

Although closely related, a CSR and a digital certificate serve different purposes.

Feature  Certificate Signing Request (CSR)  Digital Certificate 
Purpose  Requests a certificate from a CA  Verifies identity after issuance 
Created by  Certificate requester  Certificate Authority 
Contains  Public key and identity information  Public key, identity information, and CA signature 
Usage  Used during certificate enrollment  Used for authentication and encrypted communications 

Understanding this distinction helps organizations manage certificate issuance more effectively.

How Hexnode supports certificate-based security

Organizations widely use digital certificates for enterprise authentication, secure network access, and device identity. Hexnode UEM enables administrators to centrally deploy certificates to supported devices and apply device management policies that support certificate-based security. This centralized approach reduces repetitive endpoint-level configuration and helps organizations support certificate-based authentication across managed devices.

FAQs

The entity requesting a digital certificate, such as a server, device, application, or organization, generates a CSR and submits it to a Certificate Authority for validation and certificate issuance.