projectdiscovery/nuclei · error

failed to parse PEM block containing the private key

Error message

failed to parse PEM block containing the private key

What it means

Error "failed to parse PEM block containing the private key" thrown in projectdiscovery/nuclei.

Source

Thrown at pkg/templates/signer/handler.go:105

		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
		gologger.Info().Msgf("Private Key is encrypted with passphrase")
		fmt.Printf("[*] Enter passphrase (exit to abort): ")
		bin, err := term.ReadPassword(int(os.Stdin.Fd()))
		if err != nil {
			return err
		}
		fmt.Println()
		if string(bin) == "exit" {
			return fmt.Errorf("private key requires passphrase, but none was provided")
		}
		block.Bytes, err = x509.DecryptPEMBlock(block, bin) // nolint: all
		if err != nil {
			return err
		}
	}

View on GitHub (pinned to 265b3a3dec)

When it happens

Trigger: Thrown at pkg/templates/signer/handler.go:105 when the library encounters an invalid state.

Common situations: See trigger scenarios.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

AI-assisted analysis of projectdiscovery/nuclei@265b3a3dec (2026-08-15). Data as JSON: /api/errors/8d499ed97ad25ddc. Report an issue: GitHub.