How do you keep every certificate in your organization playing by the same security rules? For many teams, that’s easier said than done. The good news: you already have a built-in way to enforce consistency: Certificate Signing Requests (CSRs).
A CSR helps standardize key sizes, algorithms, and identity fields so every certificate meets your organization’s security and compliance requirements.
You’ll generate a CSR whenever you need a new certificate from a certificate authority (CA). Once approved, the CA provides the certificate containing the public key and identifying information, while the private key remains secure on the requester’s system. CSRs are required at multiple stages of the certificate management lifecycle: issuance, renewals that involve new key pairs, or when upgrading your organization to new cryptographic standards, among others.
So when do you need to generate a CSR?
In this article, we’ll identify where in the certificate management lifecycle you might need a certificate and how to use CSRs for consistent policy enforcement across your organization.
When to generate a CSR
There are several stages of the certificate management lifecycle when you’ll need to request a new or updated certificate.
Initial issuance
You’ll generate a new CSR the first time you need a certificate to stand up a new web server, VPN, or internal application. For example, requesting a TLS certificate from a public CA like DigiCert or Let’s Encrypt requires a CSR as the input.
Add any new CSRs to your organization’s PKI key inventory, so you can monitor when it is time for renewal.
Renewals with new key material
Certificates approaching expiration need to be renewed or retired, and many policies require rolling over keys concurrently. When you need a new key pair, you need a new certificate. Generating a fresh CSR means the new private key is unique, preventing cryptographic reuse.
If any keys have been exposed in a data breach, you should renew all impacted certificates to prevent unauthorized access. Essentially, it’s like changing passwords to make sure someone with the outdated password (or key) cannot access your resources.
Upgrading cryptographic strength
In addition to renewing certificates, you can (and should) upgrade the protective algorithms used by your organization. Cryptographic algorithms are evolving as decryption technologies mature, forcing organizations to update their algorithms or risk data breaches and other security incidents when outdated algorithms are decrypted.
The public key changes when your organization moves between algorithms, which requires a new CSR to get an upgraded certificate. These upgrades will continue to be popular as weaker algorithms become deprecated and therefore more risky.
Another reason organizations need to consider upgrading algorithms is post-quantum cryptography (PQC), which covers how cryptography will need to evolve when quantum computing is mature enough technology. Most algorithms would be decrypted by quantum computers in no time at all, meaning your organization should already be reviewing its cryptographic algorithms in preparation for PQC. Get rid of certificates using outdated algorithms in favor of more secure ones.
CA or infrastructure migrations
When an org changes its PKI infrastructure, including transitioning from an on-premises solution to the cloud, the CA hierarchy changes. Every system will need to generate a CSR again to re-establish trust.
Ensure you’ve accounted for all existing certificates before a major CA or infrastructure migration, and update them as quickly as possible (with an automated tool).
Automated DevOps environments
When automating your DevOps pipeline, you’ll need a lot of short-lived temporary certificates. Kubernetes workloads typically use Automated Certificate Management Environment (ACME) or Enrollment over Secure Transport (EST) protocols to dynamically generate CSRs and request short-lived certificates. The process happens at machine speed, but the principle is the same—a CSR is still required for every certificate.
Keep your DevOps pipelines running smoothly by automating CSR generation alongside other processes.
IoT and device identity
Internet of things (IoT) devices generate CSRs locally during manufacturing or provisioning to confirm their identities and get certificates. For example, a smart medical device generates a CSR to request its identity certificate before it can connect to a hospital network.
Make sure to evaluate algorithms for security to ensure IoT devices do not put users at risk for security incidents.
How are CSRs generated?
Generating a CSR is vital to protecting the root of trust for every certificate your organization uses, particularly for purposes like code signing. When you generate a CSR, you’re essentially creating a new key pair. The public half of the pair goes in the request, and the private half stays local.
The process involves two basic steps:
- Generate a CSR. CSRs bundle details like the Common Name (CN), Subject Alternative Names (SANs), organizational details, and sometimes extensions like key usage or signature algorithms. Ensure your CSRs are set to the proper algorithms and match the settings used across your organization.
- The CA issues a certificate. The CA verifies the information in your CSR, signs it, and issues a certificate that binds the public key to an identity.
- If the CSR is malformed (wrong SANs, weak algorithms), the CA either rejects it or issues a certificate that fails to meet security and compliance requirements.
Once this process is complete, your secure certificate should be updated. Ensure the certificates are stored securely, and test to ensure they meet your organization’s security and compliance requirements.
Common pitfalls (and suggested solutions) of CSR generation
When you generate a CSR to enforce security policies across your organization, you include a lot of data for the CA to verify. If that data is missing or incorrect, your business may not be able to issue or renew vital certificates before they expire.
Here are some common CSR pitfalls and suggested solutions.
| Pitfall | Solution |
| Missing or incorrect subject alternative names (SANs). Modern browsers and clients rely on SANs instead of CNs, so CSRs without them can cause outages. | Automate CSR generation with a certificate management platform to eliminate typos, ensure proper SANs, and enforce consistent templates. |
| Distributed and non-standardized PKI. Some tools default to deprecated algorithms when generating CSRs, so the resulting certificates fail compliance audits. Across the organization, different teams may generate CSRs with inconsistent naming conventions or field structures. | Standardize CSR templates to help every team generate requests with the same approved algorithms, organization information, naming conventions, etc. This helps accelerate and reduce the cost of audits. |
| Insecure key storage. When private keys are generated on a shared build server or copied between machines, they could be accessed by unauthorized parties, threatening the security of your organization’s data. | Secure keys in the system they’re created in and use hardware security modules (HSMs), key vaults, or secure enclaves to keep them locked down. CSRs should also be kept secure and encrypted if possible. |
| Manual CSR generation. Without automation, renewal CSRs are often generated late, creating a scramble to issue and deploy new certificates before the old ones expire. Demand for certificates is high and increasing due to user and device growth. | Track every certificate in your organization including their expiration dates using automated certificate management platforms. We also recommend using APIs like ACME or EST to generate CSRs automatically at scale where needed, such as DevOps or IT environments. |
How CSR generation fits into mature certificate management
The certificate management lifecycle is massive, integrated and interwoven in modern environments, and vital to smooth operations. Every single certificate needs to be requested, issued, tracked, deployed, renewed before expiration, and eventually retired. And most organizations deal with tens of thousands, if not millions, of certificates. Mismanaged certificates become sources of security breaches and outages that cost organizations thousands.
CSR generation is a critical step to ensure your certificates are valid, up-to-date, and secure. Discovery and inventory processes help ensure every certificate is accounted for, but CSRs are where new certificates originate. Certificate management tools should help automate CSR generation wherever possible.
Mature, automated workflows extend from CSR creation throughout the entire certificate lifecycle: issuance, provisioning, renewal, and revocation. The easiest place to enforce your organization’s certificate governance policies, from key size to algorithm choice, is before the certificate is issued. Generating a CSR with the right settings and information will ensure resulting certificates can pass security audits.
Treat CSR generation as an automated, policy-driven process. Keyfactor Command certificate management can help by discovering every certificate, automating renewals, and preventing costly outages, all from a single platform built to scale. Simplify your PKI operations and give your team time back to focus on what matters.
