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U-Boot: Insert Backdoor Shell into FS

iot-security-device-attacks-bootloader | Level: Easy  | Total Lab Runs: 0 | Free Lab

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During a pentest you've uncovered a terminal server endpoint served over the web - this endpoint is connected to the console port of an embedded device. Your task is to get a shell on the device by a running a backdoor on it. More information is provided below:

The terminal server available at "http://vexpress.arm:9000" provides access to the console port of the embedded device. Once the embedded device boots into the Linux system, the system password is not available. Hence, it is important to backdoor the system so that the attacker can gain access to the password protected system.

Objective: Backdoor the embedded device, get a shell on it and retrieve the flag!


  • The IP address of your Kali machine should be 192.X.Y.2
  • The terminal server should be located at 192.X.Y.3 (vexpress.arm)
  • The remote TFTP should be located at 192.X.Y.4 (tftp.server)
  • Reloading the web-session of the terminal server will reset the embedded device.
  • The files given in /root/Desktop/backdoor-files of Kali machine will help you in the task

1. Flag

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