XTLS/Xray-core · error

failed to generate serial number

Error message

failed to generate serial number

What it means

Error "failed to generate serial number" thrown in XTLS/Xray-core.

Source

Thrown at common/protocol/tls/cert/cert.go:139

	parentKey = selfKey
	if parent != nil {
		if _, e := asn1.Unmarshal(parent.PrivateKey, &ecPrivateKey{}); e == nil {
			pKey, err = x509.ParseECPrivateKey(parent.PrivateKey)
		} else if _, e := asn1.Unmarshal(parent.PrivateKey, &pkcs8{}); e == nil {
			pKey, err = x509.ParsePKCS8PrivateKey(parent.PrivateKey)
		} else if _, e := asn1.Unmarshal(parent.PrivateKey, &pkcs1PrivateKey{}); e == nil {
			pKey, err = x509.ParsePKCS1PrivateKey(parent.PrivateKey)
		}
		if err != nil {
			return nil, errors.New("failed to parse parent private key").Base(err)
		}
		parentKey = pKey
	}

	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
	if err != nil {
		return nil, errors.New("failed to generate serial number").Base(err)
	}

	template := &x509.Certificate{
		SerialNumber:          serialNumber,
		NotBefore:             time.Now().Add(time.Hour * -1),
		NotAfter:              time.Now().Add(time.Hour),
		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
		BasicConstraintsValid: true,
	}

	parentCert := template
	if parent != nil {
		pCert, err := x509.ParseCertificate(parent.Certificate)
		if err != nil {
			return nil, errors.New("failed to parse parent certificate").Base(err)
		}
		parentCert = pCert

View on GitHub (pinned to 7d214f8b09)

When it happens

Trigger: Thrown at common/protocol/tls/cert/cert.go:139 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of XTLS/Xray-core@7d214f8b09 (2026-08-15). Data as JSON: /api/errors/9ba82b852664672a. Report an issue: GitHub.