Trezor’s multi -layered defense for supply chain attacks | Satoshilabs | March 2025

In Trezor, we pioneered the first hardware wallet in 2013 with a clear goal to provide safe and easy to use tools for managing bitcoin and encryption. The hardware wallet is designed to protect it from remote attacks by keeping a private key offline. Previous models are always excellent.

Hardware wallets offer powerful security, but no system is entirely immunity to physical attacks. Given enough time, expertise and resources, the determined attacker can try to extract a private key from the theoretically stolen device. To alleviate this risk, we have introduced a user -defined additional security class for a wallet backup. Unlike wallet backups, passwords are not stored in the device, so they cannot be extracted even if a physical attack occurs.

One of the biggest differences in Trezor Safe Family (introduced by the launch of Trezor Safe 3 in 2023) was the introduction of dedicated security elements. In the case of devices theft or loss, it has been introduced as a response to user feedback for enhanced protection. The security elements used in Trezor Safe 5 and Trezor Safe 3 are Optiga ™ Trust M (V3). In fact, it is a chip designed to protect very sensitive information from software and hardware attacks.

All Trezor models are kept safe for remote attacks, but the security elements of the Trezor Safe 3 & Trezor Safe 5 add an additional physical security layer. For example, if the Trezor device is lost or stolen.

The security elements of Trezor Safe 3 & Trezor Safe 5 provide protection measures:

• Improved pin protection: In case of theft, unauthorized access.
• Prevention of seed extraction by defect injection attack (voltage defect): previously known problems in Trezor Model One and Trezor Model T.
• Device Verification: Strengthen resistance to supply chain attacks.

Supply chain attacks occur when the device is altered before reaching the customer. This may include an attacker to modify and resell legal devices.

Trezor has implemented several defensive classes to confront the risk of supply chain.

1. Firmware security check
   no way. Firmware Revised ID Check
   rain. Firmware hash check
2. On boarding protection
   no way. Pre -installed firmware detection
   rain. Entropy Inspection Workflow
   aspirate. Firmware upgrade
   d. Device verification check
3. Firmware security check
   no way. Firmware Revised ID Check

Trezor Suite contains multiple layers of verification layers to detect potential modulation. This includes:

no way. Firmware Revised ID Check

The firmware revision is a unique identifier allocated to each firmware release. Whenever the Trezor device is connected, the Trezor Suite checks the firmware revision for the official release database. The operation method is as follows.

• If the firmware revision does not match, the Trezor suite displays the device as a counterfeit.
• This inspection is especially effective for supply chain attacks that require long preparation time. This is due to the time it takes to modify and deploy modified devices.
• Trezor regularly launches a new firmware update and the Trezor Suite prompts the firmware to update the firmware before setting the firmware, so the device that executes the unauthorized firmware may fail.

Important: Actually, we recommend that we always update the firmware of the device regularly. It is necessary to expand the function of Trezor, apply new security measures, and activate the newly developed functions.

Here are as follows:

rain. Firmware hash check

The firmware hash confirmation is an encryption verification process that ensures the integrity of the firmware running on the treasure device. This is how it works.

• When connecting all the devices, the Trezor Suite issues any encryption problem for the device.
• The device then calculates the firmware hash, which is compared with the expected hash of the official firmware binary file stored in the Trezor Suite.
• If the results do not match, the Trezor Suite displays the device as a counterfeit.

This inspection is effective only if the device runs the latest firmware version. This is why Trezor Suite strongly recommends users to update the firmware regularly.

Here are as follows:

All TREZOR devices have additional security tests during the initial settings.

no way. Pre -installed firmware detection

• When the device is detected with the pre -installed firmware, the user will be asked to check whether the device is used.
• If the device has not been used before, the device may be damaged and the user is warned accordingly.

rain. Entropy Inspection Workflow

During the wallet creation, the Trezor uses the random data (entropy) in the two sources to create a wallet.

1. Treasure: Inner source.
2. Companion App: Typically, it is a Trezor Suite, but it may be other compatible apps such as Trezorctl or Electrum.

Fake or damaged devices generally ignore the input of an external entropy sauce and generate a wallet in a predictable crystalline way to reproduce and access the attacker.

Entrophy tests protect the user from this operation and display the device as a counterfeit if they do not pass through the check.

Here are as follows:

aspirate. Firmware upgrade

• During on boarding, the user upgrades to the latest firmware version and triggers both revised ID and hash tests, as described in the previous part of the article.
• The user has an opt -out option, but it is better not to do so in light of the security risk of using old firmware.

d. Device verification check

For Trezor Safe 3 and Trezor Safe 5, security elements play an important role in checking the authenticity of the device.

When setting up the device:

• Trezor Suite sends a challenge to the device.
• Security elements are signed by challenges and returned to their own device certificates.
• Trezor Suite checks the two signatures and checks the authenticity.

The certificate is confirmed only locally and is immediately discarded to ensure personal information. The user can reject the device authentication process, but it is strongly recommended.

Learn more:

no way. Tamper notification packaging

All Trezor Safe 3 provides hologram seals to the connector so that the device is not disturbed before reaching the customer. There is no seal in the Trezor Safe 3 packaging.

Depending on the time the device is manufactured and packaged, the following:

The signs of damaged or missing seals are the powerful indicators that the device is damaged. In this case, please contact Trezor SUPPORT through the chatbot HAL.

The director Donjon Team demonstrated how to bypass firmware hash in Trezor Safe 3 using advanced voltage defect technology. Other measures for supply chain attacks are still not challenged. But it is important to pay attention.

• You can’t use this attack to hack a private key or extract the pin.
• Attacks must be completely physically accessible to the device. (This includes reconstruction of the device, re -assembling the device without leaving a significant sign of modulation, using a special tool, using a special tool, using a special tool.)
• If the device is purchased from the official source, it is unlikely to be tampered with.

This emphasizes why we always recommend purchases Trezor.io Or approved resellers.

Self -sustaining with hardware wallets such as Trezor is the safest way to store encryption.

• Trezor has your own key.
• No exchange can freeze funds.
• A third party cannot access the wallet.

The actual risk is to trust the third party. In this case, we buy a Trezor hardware wallet beyond the official listed source.

In the worst supply chain attack scenario, attackers still need to modify and distribute the device unrealistically.

no. If you buy a device from the official source, there is little likely to have a problem with the device. If you have a sign of modulation when your order arrives or you are purchased from an unauthorized reseller, you will be able to contact you if you contact Trezor support or start a discussion at Trezor Forum.

• Your funds are kept safe and you do not need your actions.
• Safe elements provide additional levels of protection for physical attacks.
• Our built -in supply chain defense includes multiple security classes.
• Trezor Suite makes it almost impossible to deploy modified devices in scale.

Security is never static, and Trezor continues to take measures to improve hardware and software. The study of LEDGER DONJON emphasized one possible attack vector. But it does not undermine the core security of the Trezor Safe Family.

Trezor completely accepts such security studies because it helps to strengthen the ecosystem. We will continue to improve security measures and keep them completely transparent for potential risks.

Finally, it is recommended to buy Trezor hardware wallets or accessories directly. Trezor.io Or resellers approved as an example case for your security.

As always, keep the information and keep it safe!