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T1205: Port Knocking II

mitre-persistence | Level: Easy  | Total Lab Runs: 0 | Premium Lab

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Port Knocking is a well-established method used by both defenders and adversaries to hide open ports from access. To enable a port, an adversary sends a series of packets with certain characteristics before the port will be opened.

In this lab, the remote server has deployed port knocking to protect SSH service. The port knocking pattern is deployed on the following ports.

  • 11011
  • 11012
  • 11013
  • 11014
  • 11015

The knock uses TCP packets with one of four TCP flags (i.e. SYN, RST, URG, FIN) set.

When 'n' number of packets are sent on each port, the SSH service will become accessible. Then, the user has to figure out the SSH credentials to access the remote server.

Objective: Figure out the port knocking pattern, perform the knock, SSH into the remote server and retrieve the flag! 


  • This lab is dedicated to you! No other users are on this network :)
  • Once you start the lab, you will have access to a Kali CLI instance.
  • Your Kali instance has an interface with IP address 192.X.Y.2. Run "ifconfig" to know the values of X and Y.
  • The target machine is accessible on IP address 192.X.Y.3.
  • Do not attack the gateway located at IP address 192.X.Y.1
  • Password dictionary to use: /root/wordlists/100-common-passwords.txt
  • hping3 is installed on Kali CLI machine
  • Here the number 'n' is such that 1 < n < 5 
  • Username for SSH account on the remote target machine is 'admin'.

1. Flag

The following activities are strictly prohibited on this website unless otherwise explicitly stated as allowed in the mission statement:

  • Using automated scanners
  • Using brute force attacks
  • Denial of Service attacks
  • Attacking other student machines in challenges where you might achieve a shell on the vulnerable system
  • Attacking the lab infrastructure

Users violating the above will be either temporarily or permanently banned from the website. 

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