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GCIH · Question #734

Which netcat command will listen on port 2222 for connections from a remote system (10.0.0.1)?

The correct answer is D. C:\>nc.exe -1-p 2222. The netcat -l flag activates listen mode and -p specifies the port number, making nc.exe -l -p 2222 the correct command to open a listener on port 2222.

Vulnerability Exploitation & Privilege Escalation

Question

Which netcat command will listen on port 2222 for connections from a remote system (10.0.0.1)?

Options

  • AC:>nc.exe > p 2222
  • BC:>nc.exe 10.0.0.1 2222
  • CC:>nc.exe -z -p 10.0.0.1 2222
  • DC:>nc.exe -1-p 2222

How the community answered

(22 responses)
  • A
    5% (1)
  • B
    5% (1)
  • D
    91% (20)

Why each option

The netcat -l flag activates listen mode and -p specifies the port number, making nc.exe -l -p 2222 the correct command to open a listener on port 2222.

AC:\>nc.exe > p 2222

The > character is a shell output redirection operator, not a netcat flag; this command would attempt to redirect output to a file named 'p' rather than configuring any listening behavior.

BC:\>nc.exe 10.0.0.1 2222

Providing nc.exe with an IP address and port in client mode (nc.exe 10.0.0.1 2222) initiates an outbound connection to a remote host - it does not create a local listener.

CC:\>nc.exe -z -p 10.0.0.1 2222

The -z flag enables zero-I/O scan mode, which is used for port scanning to check if ports are open without sending data, not for establishing a persistent listener.

DC:\>nc.exe -1-p 2222Correct

The nc.exe -l -p 2222 command uses -l to place netcat into server listen mode, causing it to wait passively for an inbound connection rather than initiating one. The -p flag designates port 2222 as the listening port, which is the standard Windows netcat syntax for hosting an inbound connection.

Concept tested: Netcat listen mode syntax with -l and -p flags

Source: https://nmap.org/ncat/guide/ncat-usage.html

Topics

#netcat#port listener#reverse shell#network tools

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