projectdiscovery/nuclei · error

dialers not initialized for %s

Error message

dialers not initialized for %s

What it means

An executionId was found but protocolstate.GetDialersWithId(executionID) returned nil: no fastdialer set is registered for the execution (never initialized, already torn down, or an id mismatch). The HTTP path refuses to fall back to a default dialer, so it fails closed.

Source

Thrown at pkg/js/libs/http/http.go:272

		return nil, fmt.Errorf("http: executionId not set")
	}

	parsed, err := url.Parse(rawURL)
	if err != nil {
		return nil, fmt.Errorf("http: invalid url: %w", err)
	}
	if parsed.Scheme == "" || parsed.Host == "" {
		return nil, fmt.Errorf("http: url must include scheme and host")
	}

	host := parsed.Hostname()
	if !protocolstate.IsHostAllowed(executionID, host) {
		return nil, protocolstate.ErrHostDenied.Msgf(host)
	}

	dialers := protocolstate.GetDialersWithId(executionID)
	if dialers == nil {
		return nil, fmt.Errorf("dialers not initialized for %s", executionID)
	}

	tlsConfig := &tls.Config{
		InsecureSkipVerify: true,
		MinVersion:         tls.VersionTLS10,
		Renegotiation:      tls.RenegotiateOnceAsClient,
	}
	if host != "" {
		tlsConfig.ServerName = host
	}

	transport := &http.Transport{
		Proxy: http.ProxyFromEnvironment,
		DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
			return dialers.Fastdialer.Dial(ctx, network, addr)
		},
		DialTLSContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
			return dialers.Fastdialer.DialTLSWithConfig(ctx, network, addr, tlsConfig)

View on GitHub (pinned to 265b3a3dec)

Solutions

1. Initialize protocolstate dialers for the execution before any request
2. Keep Client construction and requests inside a single execution; never cache a Client across scans
3. Cancel or await in-flight requests before execution teardown

Example fix

// before: client (and its execution) already torn down when this runs
const resp = client.Get('https://example.com');

// after: create and use the client within one execution
const client = new http.Client();
const resp = client.Get('https://example.com');
// execution ends after the template run, not before

try {
  const resp = client.Get(url);
} catch (e) {
  if (/dialers not initialized/.test(e.message || '')) {
    // execution lifecycle bug: create the Client and request inside one live execution
  }
}

When it happens

Trigger: SDK/test usage that sets an executionId but skips protocolstate initialization; requests still in flight when the execution's dialers were released; a Client held across execution boundaries.

Common situations: Same lifecycle-mismatch class as the grpc 'dialers not initialized' error: embedded usage bypassing engine init, goroutines outliving the scan, or executions cleaned up while JS callbacks still run.

Related errors

• grpc: dialers not initialized for executionId %q
• http: executionId not set
• goimpacket: no fastdialer registered for executionId %q
• grpc: refusing to dial without executionId
• http: invalid url: %w

AI-assisted analysis of projectdiscovery/nuclei@265b3a3dec (2026-08-15). Data as JSON: /api/errors/c5951bf9beb3a6c5. Report an issue: GitHub.