kubernetes/kops · error

error creating certificate: %v

Error message

error creating certificate: %v

What it means

Fires when x509.CreateCertificate fails while producing the signed certificate bytes in signNewCertificate — e.g. unsupported key/algorithm combination, mismatched parent/signer key, or invalid template fields.

Source

Thrown at pkg/pki/csr.go:92

	if signer != nil {
		parent = signer
	} else {
		parent = template
		signerPrivateKey = privateKey
	}

	if template.KeyUsage == 0 {
		template.KeyUsage = x509.KeyUsageDigitalSignature | x509.KeyUsageKeyEncipherment
	}

	if template.ExtKeyUsage == nil && !template.IsCA {
		template.ExtKeyUsage = []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth}
	}
	// c.SignatureAlgorithm  = do we want to override?

	certificateData, err := x509.CreateCertificate(crypto_rand.Reader, template, parent, template.PublicKey, signerPrivateKey.Key)
	if err != nil {
		return nil, fmt.Errorf("error creating certificate: %v", err)
	}

	cert, err := x509.ParseCertificate(certificateData)
	if err != nil {
		return nil, fmt.Errorf("error parsing certificate: %v", err)
	}

	c := &Certificate{
		Subject:     cert.Subject,
		IsCA:        cert.IsCA,
		Certificate: cert,
		PublicKey:   cert.PublicKey,
	}

	return c, nil
}

View on GitHub (pinned to 4c8573c808)

Solutions

1. Check the wrapped %v error for the x509 cause (algorithm, key type, template field)
2. Ensure the signer private key matches the signer certificate's public key
3. Validate template fields (KeyUsage, ExtKeyUsage, validity) are consistent with the key type

When it happens

Trigger: Thrown at pkg/pki/csr.go:92 when the library encounters an invalid state.

Common situations: See trigger scenarios.

Understand the failure class

• SSL/TLS and certificate errors — how TLS handshakes and certificate validation fail.

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/602b366e7608038c. Report an issue: GitHub.