projectdiscovery/nuclei · error

invalid certificate: expected common name to be set

Error message

invalid certificate: expected common name to be set

What it means

Error "invalid certificate: expected common name to be set" thrown in projectdiscovery/nuclei.

Source

Thrown at pkg/templates/signer/handler.go:90

	if privateKey, err := os.ReadFile(filepath.Join(dir, PrivateKeyFilename)); err == nil {
		k.PrivateKey = privateKey
		return nil
	}
	return ErrNoPrivateKey
}

// ParseUserCert parses the user certificate and returns the public key
func (k *KeyHandler) ParseUserCert() error {
	block, _ := pem.Decode(k.UserCert)
	if block == nil {
		return fmt.Errorf("failed to parse PEM block containing the certificate")
	}
	cert, err := x509.ParseCertificate(block.Bytes)
	if err != nil {
		return err
	}
	if cert.Subject.CommonName == "" {
		return fmt.Errorf("invalid certificate: expected common name to be set")
	}
	k.cert = cert
	var ok bool
	k.ecdsaPubKey, ok = cert.PublicKey.(*ecdsa.PublicKey)
	if !ok {
		return fmt.Errorf("failed to parse ecdsa public key from cert")
	}
	return nil
}

// ParsePrivateKey parses the private key and returns the private key
func (k *KeyHandler) ParsePrivateKey() error {
	block, _ := pem.Decode(k.PrivateKey)
	if block == nil {
		return fmt.Errorf("failed to parse PEM block containing the private key")
	}
	// if pem block is encrypted , decrypt it
	if x509.IsEncryptedPEMBlock(block) { // nolint: all

View on GitHub (pinned to 265b3a3dec)

When it happens

Trigger: Thrown at pkg/templates/signer/handler.go:90 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 projectdiscovery/nuclei@265b3a3dec (2026-08-15). Data as JSON: /api/errors/a5d031d2e6874c0f. Report an issue: GitHub.