projectdiscovery/nuclei · error

no response received

Error message

no response received

What it means

Thrown by telnet.DetectNTLM when the read returns successfully but zero bytes (n == 0 with no error). This means the peer closed its sending side or delivered an empty segment — the connection is up at the TCP level but the server contributed nothing to the NTLM exchange, so there is no response to parse.

Solutions

1. Verify the service is telnet and supports MS-TNAP/NTLM before probing
2. Treat 'no response' as negative evidence (no NTLM info) instead of an abort
3. Combine with a banner grab first to confirm the service identity

try { client.DetectNTLM(host, port) } catch (e) { if (String(e) === 'no response received') { /* server sent nothing: no NTLM info */ } else { throw e; } }

When it happens

Trigger: Server closes the connection immediately after receiving the MS-TNAP login packet; half-close behavior where the service shuts its write side; middlebox acknowledging TCP but suppressing payloads.

Common situations: Hardened telnet services dropping unrecognized option packets silently; devices that reset state on protocol violations without an RST visible to the reader; probes against services that are not telnet at all.

Related errors

• failed to send MS-TNAP login packet
• failed to parse NTLM response
• failed to read response
• authentication failed
• prompt not found (read cap reached)

AI-assisted analysis of projectdiscovery/nuclei@265b3a3dec (2026-08-15). Data as JSON: /api/errors/4f0bcc0c446dc9a8. Report an issue: GitHub.

Appendix: source

Thrown at pkg/js/libs/telnet/telnet.go:264

	// Use the MS-TNAP packet crafting functions from our telnetmini library
	// Create MS-TNAP Login Packet (Option Command IS) as per Nmap script
	tnapLoginPacket := telnetmini.CreateTNAPLoginPacket()

	// Send the MS-TNAP login packet
	_, err = conn.Write(tnapLoginPacket)
	if err != nil {
		return nil, fmt.Errorf("failed to send MS-TNAP login packet: %w", err)
	}

	// Read response data
	buffer := make([]byte, 4096)
	n, err := conn.Read(buffer)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}

	if n == 0 {
		return nil, fmt.Errorf("no response received")
	}

	// Parse NTLM response using our telnetmini library functions
	response := buffer[:n]

	// Use the parsing functions from our library instead of reimplementing
	// This should use the NTLM parsing functions we added to telnetmini
	ntlmInfo, err := telnetmini.ParseNTLMResponse(response)
	if err != nil {
		return nil, fmt.Errorf("failed to parse NTLM response: %w", err)
	}

	return ntlmInfo, nil
}

View on GitHub (pinned to 265b3a3dec)