Trezör® Bridge® — Connect Your Web3 World Securely™

Executive summary

Trezör® Bridge® is a local software component designed to act as a secure conduit between a Trezör hardware wallet and web-based applications that require hardware-backed signing (for example, browser wallets, dApps, and web-based management interfaces). Running on your machine, Bridge exposes a controlled local API (via localhost) that web pages can use to detect a connected device, request public keys, and send transactions for on-device review and signing. The Bridge architecture is deliberately minimalistic: it avoids transmitting secrets over the web, requires explicit user interaction for approvals, and relies on signed firmware and device-level UI confirmation as the ultimate security anchor.

This guide explains how Bridge works, how to install and configure it safely, developer considerations for integrating with Bridge, and practical operational security recommendations for Web3 users.

What is Trezör® Bridge® and why it matters

As decentralized applications moved into browsers, a secure, reliable way to connect physical wallets to web pages became necessary. Trezör® Bridge® solves this by:

• Providing a local transport (typically WebSocket or HTTP to localhost) for web pages to communicate with attached hardware devices.
• Isolating low-level USB or Bluetooth device interactions from the browser, which historically had inconsistent support across platforms.
• Ensuring that any transaction or message to be signed is shown on the hardware device for user verification — preventing host or web-level tampering.
• Serving as a small, auditable runtime with minimal privileges, reducing the attack surface compared to broader system services.

The Bridge model balances usability — seamless integration with dApps — with principled security: your private keys never leave the device and each signing action requires an on-device confirmation that you explicitly approve.

Supported platforms & prerequisites

Trezör Bridge runs locally on major desktop platforms. Before installing, verify the following:

• Supported OS: Windows, macOS, and many popular Linux distributions.
• Browser: modern browsers with WebUSB/WebHID/WebSocket capabilities; Bridge often offers compatibility shims for broad support.
• Device: a compatible Trezör hardware wallet (Model T, Model One, or other supported variants).
• USB cable: a data-capable cable (not all USB cables support data transfer; charging-only cables will not work).
• Administrator or user-level permission to run local background processes (some OSes will prompt to allow Bridge to run and to accept network bindings to localhost).

Always obtain the Bridge installer from the official Trezör distribution point. Avoid third-party mirrors or links received over unsolicited channels to reduce supply-chain risk.

Installing Trezör® Bridge® — step-by-step

Follow these steps for a safe installation. The exact UI may change with newer distributions — follow the official prompts shown by the installer.

1. Download the latest Bridge installer from the official Trezör website or verified download page.
2. Verify the integrity of the download if checksum/signature files are provided (recommended for high-value setups).
3. Run the installer and follow on-screen steps; the installer will configure a local service that listens to localhost ports and register any necessary device drivers where required.
4. On first run, your OS and browser may prompt for permission to use USB devices or to allow local network access — accept only if you initiated the install and trust the source.
5. Connect your Trezör device using a data-capable USB cable. Bridge should detect the device and offer a ready state for web apps to connect.

If Bridge offers an auto-start/background service, you can enable it for convenience. Advanced users may prefer manual startup for stricter control over active services.

How the communication flow works (high-level)

Understanding the flow helps you reason about security and where to check for issues:

1. Web page → Bridge discovery: A dApp running in the browser connects to localhost (Bridge) using a predetermined port or protocol. Bridge may require the web page to present an origin token or request a pairing permission first.
2. Bridge → Device transport: Bridge translates the high-level Web3 request into USB/HID/Bluetooth commands the Trezör device understands.
3. Device → User: The Trezör device displays the transaction or message details on its screen. You verify address/amount/operation directly on the device.
4. User → Device approval: You physically approve the action on the device (via button press or touchscreen). Only then does the device sign the request.
5. Signed response → Bridge → Web page: The signed payload is returned to Bridge, forwarded to the web page, and then broadcast or used as appropriate by the dApp.

At no point should the private key ever be accessible to Bridge or the browser — the device holds the signing key and only outputs cryptographic signatures after explicit user approval.

Security model and threat mitigations

Trezör Bridge is part of a layered security model. Key points:

• On-device confirmation: All sensitive operations are finalized on the device screen; verify details visually.
• Least-privilege Bridge: Bridge runs with minimal required privileges and exposes a localhost-only interface by default — web pages cannot control it remotely without local user consent.
• Origin checks & pairing: Modern Bridge implementations may require explicit pairing or origin verification before granting access to a web page.
• Firmware signing: Devices require signed firmware; never accept firmware prompts that are not presented via the official Suite/Bridge ecosystem.
• Supply-chain hygiene: Download Bridge binaries only from the official channel and verify signatures when available to mitigate compromised installers.

Users should be wary of rogue web pages that attempt to trick them into approving undesired transactions; always read and confirm fields on the device screen before approving.

Connecting to web wallets and dApps

Once Bridge is running and has detected your connected device, common steps to connect with a web wallet or dApp include:

1. Open the dApp or web wallet in your browser and select the “Connect hardware wallet” or “Connect Trezör” option.
2. The dApp will attempt to connect to Bridge, which may prompt you to allow the connection or select a device.
3. Choose the account/address you wish to expose to the dApp. Only public keys and addresses are shared; again, signing requires on-device confirmation.
4. When the dApp needs a signature, it will send a request through Bridge; examine the device screen and approve or reject the request.

Limit the accounts and permissions you expose to each dApp. If in doubt, disconnect and re-evaluate the request.

Developer integration notes

Developers can design dApps to communicate with Bridge using the published local API or through connector libraries. Key considerations:

• Discovery & pairing: Implement clear user prompts to initiate Bridge pairing and handle user approvals gracefully.
• Origin & permission: Where supported, request explicit origin binding so users can later audit which web origins have access to Bridge sessions.
• Graceful error handling: Handle device disconnects, timeouts, and user rejections in a user-friendly way and avoid retry loops that might confuse the user.
• Minimal prompts: Only request signatures when strictly necessary and surface clear explanations for each signature request.
• Test against multiple Bridge versions and platforms: Different OS/browser combinations may behave differently with device drivers and WebUSB/HID layers.

Refer to official developer docs and connector libraries for up-to-date API details and recommended UX patterns; these will help ensure a secure, consistent integration.

Troubleshooting common issues

Problems can arise from drivers, cables, OS permissions, or incompatible browser features. Common checks:

• Device not detected: Use a data-capable USB cable, switch USB ports, avoid hubs, and ensure the device is unlocked.
• Bridge not running: Confirm the Bridge service is active (system tray / background service) and check for OS prompts blocking localhost bindings.
• Browser permission errors: Allow browser access to USB/HID devices or use a browser recommended by the Bridge documentation.
• Stale Bridge version: Update Bridge to the latest stable release and restart the browser after installation.
• Conflicting software: Other USB management tools or virtualization software can interfere; temporarily disable them if needed.

If issues persist, consult official support channels or community resources and provide logs if requested (avoid sharing sensitive information such as seed material).

Operational security checklist

To maximize security while using Bridge and a hardware wallet:

• Download Bridge only from the official source and verify checksums or signatures when possible.
• Keep the device firmware up to date using official tooling and confirm firmware updates on-device.
• Run Bridge on a trusted machine that is kept up to date and free from malware.
• Never enter your recovery seed into a browser or computer — seed entry should only happen on the device during a controlled restore flow.
• Verify every transaction on the physical device display before approving; do not rely solely on the web UI copy.
• When finished interacting with a dApp, disconnect or revoke the Bridge session from the dApp to reduce persistent access surface.

FAQ

Disclaimer

This document is an informational guide that explains general concepts and recommended practices for using a hardware wallet bridge. It is not an official product manual and should not replace official documentation. Always consult the official Trezör documentation, release notes, and support channels for precise installation instructions, version compatibility, and security advisories. Never expose or share your recovery seed; treat it as the single secret to safeguard your crypto holdings.