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Bootloader Warmup Lab

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

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Lab Walkthrough Video:

Embedded device bootloaders can be very tricky to work with! This is why researchers use tools like QEMU to emulate devices. This lab will serve as a warmup to understanding how to use QEMU. Please follow the instructions below:

In this lab, the components needed to emulate an ARM vexpress-a9 device using Qemu are provided. These components are:

Initial RAM image
Disk image

 Qemu for ARM i.e. qemu-system-arm is installed on the machine. Use this setup to perform the following activities:

Activity I: Boot the device using provided U-boot and answer the following:

  1. How much time U-boot waits before starting the next stage (i.e. booting kernel)
  2. What is the version of the given U-boot?
  3. What is the value stored in U-boot environment variable "loadaddr"?
  4. What is the value of baudrate (in bps)?
  5. What command can be used to boot Linux zImage image from memory?

Activity II: Boot the device and retrieve the flag kept in /root directory of the disk image. The credentials for the emulated machine are: 

  • Username: root
  • Password: root


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. 

If you are unsure about an activity, then please contact support to confirm that it is allowed on our website.

Technical Support for this Lab:

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