If your BitBox02 shows “Bootloader” during setup, this is normal.
A new BitBox02 is delivered without pre-installed firmware. During the initial setup, the BitBoxApp installs the latest official firmware on your device.
The Bootloader screen usually means that your BitBox02 is ready for this firmware installation.
If a new BitBox02 already has firmware installed before the initial setup in the BitBoxApp, do not use it. A new device should install the firmware during setup.
What is the bootloader?
The bootloader is a small built-in program on your BitBox02.
It starts before the firmware and controls how firmware is installed and started on the device. During first-time setup, the bootloader allows the BitBoxApp to securely install the firmware.
Seeing “Bootloader” does not mean that your BitBox02 is broken. In most cases, it simply means that the device has not completed firmware installation yet.
What is firmware?
Firmware is the software that runs directly on your BitBox02.
It allows the device to work securely, communicate with the BitBoxApp, and guide you through wallet setup and confirmation steps on the device screen.
Because the BitBox02 is shipped without firmware, the firmware is installed when you set up the device for the first time.
Why the bootloader is important
The bootloader helps protect your BitBox02 during firmware installation and startup.
It checks that the firmware is valid before accepting or running it. This helps prevent unauthorized firmware from being installed on the device.
The bootloader also helps enforce important firmware rules, such as:
- accepting only firmware signed by Shift Crypto
- preventing firmware downgrades
- preventing firmware for the wrong BitBox02 edition from being installed
This means, for example, that firmware for a BitBox02 Multi cannot simply be installed on a BitBox02 Bitcoin-only device, or the other way around.
How the bootloader helps protect against malicious firmware
A malicious firmware could try to change how the device behaves. For example, it could try to manipulate what is shown on the device screen or how sensitive operations are handled.
To reduce this risk, every official BitBox02 firmware version must be signed by Shift Crypto. Before accepting new firmware, the bootloader checks these signatures.
The bootloader is one part of the BitBox02 security model. It helps ensure that only valid firmware can be installed and started on the device.
For a deeper technical explanation, see the official security documentation:
→ BitBox02 security features
Binary transparency and the firmware hash
The bootloader can also display the hash of the installed firmware before running it.
This is useful for users who want to verify which firmware is installed on their BitBox02. The firmware itself can be built deterministically, which allows advanced users and independent reviewers to compare the installed firmware with the published source code.
This helps reduce the amount of trust required in the firmware distribution process.
To learn how to show the firmware hash during startup, see:
→ How to show the firmware hash on your BitBox
Firmware bugs and security hardening
Like any software, firmware can contain bugs. Some bugs could become security-relevant if a device is used with a compromised computer or malicious software.
The BitBox02 uses several protections to reduce this risk, including secure bootloader checks, firmware signature verification, memory protection, and a locked-down factory setup.
The full BitBox02 firmware code is open source, which allows independent review and responsible disclosure by security researchers.
For more technical details, see the official threat model:
→ BitBox02 threat model
What should happen during setup?
During normal setup, the BitBoxApp should recognize your BitBox02 and ask you to install the firmware.
- Open the BitBoxApp.
- Connect your BitBox02.
- Wait until the BitBoxApp recognizes the device.
- Follow the instructions in the BitBoxApp.
- Install the firmware when prompted.
Do not unplug the BitBox02 or close the BitBoxApp while the firmware is being installed.
FAQ
Is it normal that my BitBox02 shows “Bootloader”?
Yes. During first-time setup, this is expected because the BitBox02 is delivered without pre-installed firmware.
Does “Bootloader” mean my BitBox02 is broken?
No. In most cases, it means that the device is ready for firmware installation.
Why is the firmware not pre-installed?
The firmware is installed during setup so that your BitBox02 starts with the latest official firmware.
What does the bootloader do?
The bootloader starts before the firmware. It helps install firmware securely and checks that the firmware is valid before running it.
How does the bootloader protect my BitBox02?
It only accepts valid firmware signed by Shift Crypto, helps prevent firmware downgrades, and prevents firmware for the wrong BitBox02 edition from being installed.
What is the firmware hash?
The firmware hash is a unique fingerprint of the installed firmware. Advanced users can use it to verify which firmware is installed on their BitBox02.
Can I unplug the BitBox02 during firmware installation?
No. Keep the BitBox02 connected until the firmware installation is complete.