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.csr

Certificate Signing Request

Certificates & Keys

CSR is a signing request, not an issued certificate. Inspect identity/public-key details and obtain a certificate through legitimate issuance. The matching private key is managed separately and cannot be regenerated from the request.

What it is used for
Requesting a certificate for a public key and identity
What the file contains
Producer-dependent
All sections, questions and sources

Content reviewed： · Editor：Kai

Opening steps

Choose your environment or purpose to see its steps.

Inspect the request

This is separate from an issued certificate.

  1. Identify producer and encoding.
  2. Inspect subject and public key with a request parser.
  3. Compare requested extensions with the intended use.
Check the request signature

Distinguish request integrity from identity assurance.

  1. For PEM, inspect with openssl req -in sample.csr -text -verify -noout or equivalent.
  2. Inspect verification result and names.
  3. Locate the matching private key in authorized storage.
Submit to a certificate authority

Use the authority’s documented workflow.

  1. Inspect required format and application scope.
  2. Submit the request and retain the key securely.
  3. Inspect issued names, validity and matching key.

Menu labels and support vary by app, OS and version. Preserve the original before making changes.

Troubleshooting by symptom

  • Cannot use as certificate: check whether issuance is complete.
  • Wrong names: regenerate through the authorized workflow rather than editing signed bytes.
  • Lost key: review authorized backup/reissuance procedures.
  • Signature fails: inspect unchanged request/encoding.
  • Issued key mismatch: identify the matching request key.
  • CA rejects request: inspect algorithms/extensions and authority requirements.

CSR inspection / PEM–DER re-encoding

  1. Identify request type/encoding and re-encode with matching tools.
  2. Compare the request; obtain certificates through a separate legitimate issuance process.
  3. Encoding conversion does not issue a certificate; use the authority’s workflow.

Re-encoding cannot obtain CA issuance; self-signing and issued certificates have different trust conditions.

Request, key and issued certificate

Retain the separate matching private key for the issued certificate.

Example: request-signature success does not replace CA identity validation/issuance.

Source for these steps：OpenSSL Project · openssl-req / IETF / RFC Editor · RFC 7468 — Textual Encodings

Compare request and issued result

Inspect the issued names, usage and validity rather than assuming every requested extension was accepted.

Source for these steps：OpenSSL Project · openssl-req / IETF / RFC Editor · RFC 7468 — Textual Encodings

Related-format differences

Related-format differences
Format / methodRoleWhat to verify
CSRIssuance requestRequested data/signature
CRT / CERIssued certificateNames/validity
Private keyPrivate credentialSeparate storage

Handling and security

Review identity details and never submit the private key as request material; follow legitimate issuer procedures.

Questions and answers

Is CSR a certificate?

It is a request for issuance.

Does it contain the private key?

Ordinary requests carry the public key, not the private key.

Can renaming enable HTTPS?

Use legitimate issued certificates and matching components.

Does verify success mean CA approval?

It checks the request signature, not domain/organization validation or issuance.

Can I edit CSR text to correct a name?

Regenerate the signed request through the proper workflow.

Format facts: name, steward and MIME type
Formal name
Certificate Signing Request (commonly PKCS#10)
Steward / specification
IETF / issuing certificate authority workflow
MIME type
Depends on the producer or server; an extension alone does not establish a MIME type.

Primary and official sources

  • Project documentationopenssl-req

    Reference for certificate requests and self-signed certificates.

    OpenSSL Project · Link checked：
  • StandardRFC 7468 — Textual Encodings

    Defines textual encodings for certificates, keys and requests.

    IETF / RFC Editor · Link checked：