Trezor warns of a suspected implant in a wallet bought from one reseller

A hardware wallet exists to keep one secret away from the internet. Trezor now says one of its devices may have been fitted with a part that does the opposite. The claim is unconfirmed and rests on a single customer. It raises a question about the stretch between maker and buyer. The sources do not say where the device was altered.

What Trezor has said

Trezor says its security team received a responsible disclosure report on October 28, 2026, from a customer in Indonesia. He says he bought a Trezor Safe 5 in August 2026 through the marketplace Tokopedia. The seller was CryptoBilis. Trezor had listed it as an official partner in Southeast Asia until it removed the company in October 2026.

Trezor has not received the device. It has the customer's photos and description, and it interviewed him on a video call. On that basis it treats the report as credible. The company said that waiting for lab confirmation "would leave CryptoBilis buyers exposed in the meantime."

Trezor says no CryptoBilis buyer has told it of lost money. The customer who made the report had already taken his funds off the device when he spotted the problem. Trezor wallets are self-custodial, so the company cannot see anyone's balance.

How the suspected implant works

The report describes an extra circuit board inside the Safe 5. It sits between the main board and the screen. It carries a cellular module and an antenna. Trezor says it has not verified this itself.

According to the report, the board reads what the screen shows. That includes the wallet backup, which is the recovery phrase. It then transmits the phrase over a mobile network each time the device is plugged in.

The position is the point. The screen is where the wallet shows its most sensitive secret to its owner. A part placed between the main board and the screen can see what the owner sees. The attack, as described, does not need to break the wallet's software.

This helps explain Trezor's advice on old phrases. A phrase created on a tampered wallet may already have left the device. Trezor says reusing it on another device therefore does not solve the problem.

A second maker, the same reseller

Trezor acted after Ledger. Trezor says Ledger began investigating customer losses on October 9, 2026. Those customers had bought from CryptoBilis, a seller Ledger also authorized. Ledger has since confirmed that some of those devices were physically tampered with in a supply chain attack. Per The Hacker News, Ledger also said one affected customer's wallet contained an unauthorized implant meant to capture the recovery phrase at setup.

Separately, the Singapore Police Force issued an advisory on October 28. It said Ledger wallets sold at some retail stores in Singapore carried malicious hardware components. It reported at least two cases since September 10. The sources do not say the advisory names CryptoBilis or ties those stores to it.

Trezor sees a resemblance between the board in its report and the Ledger implants. It will not go further while investigations continue, because each maker designs its devices differently. It does not know who is responsible.

Keep the scope tight. This is one unconfirmed report about one Trezor device. It is not a trend across the industry. What the sources connect is a seller that supplied two makers in one region. They do not say where either device was altered. Ledger describes a supply chain attack; Trezor says its case may be a similar attack and is unconfirmed. Neither source places the tampering at a particular step.

The lesson: know who handles the box

Security reviews often look first at the maker: its audits, its firmware, its track record. That is our observation, not a finding of the sources. This case raises a question about what happens after that. The sources do not say where the devices were altered. If it was after the maker's own checks, then the buyer's protection depends on every hand the box passes through.

That is a risk between maker and buyer, and procurement can cover it. Where a device was bought can matter alongside what was bought. The case does not show that resellers are the weak point. It shows that leaders cannot assume the maker's controls reach the desk.

What Trezor tells buyers to do

Trezor's advice applies to any Trezor model, not only the Safe 5, bought from CryptoBilis since March 2026. It also applies to a device from any other store that CryptoBilis supplied, such as its Tokopedia shop. Unsure where a device came from? Trezor points to the seller's name on the receipt, or a call to its Support team.

For a device already in use, Trezor says to create a new wallet with a fresh recovery phrase and send the funds there. If no other secure hardware wallet is at hand, it says a software wallet or a familiar exchange can serve for the time being. Check the full receiving address before sending anything.

For a device not yet set up, Trezor says to leave it that way and never enter an existing recovery phrase. Keep the device and contact Trezor Support, which will ship a new one or give a voucher.

Trezor says owners cannot reliably check a device themselves. The reporter noticed a weight difference, but Trezor says small differences have other causes. It advises against weighing or opening the device. It also expects scammers to use the incident for phishing by email, letter and phone.

Questions to put to your team

Does the company, or anyone in finance, hold funds on a hardware wallet? Where was each one bought, and from which named seller? Does procurement limit purchases to the maker's own store or a short list of authorized sellers? Trezor says it has also limited its authorized sellers going forward.

Is there a written plan for a move to a fresh wallet and recovery phrase, and who signs it off? Who will tell staff that messages offering help with this incident may be scams?

A secret is only as private as the road it travels, from the factory to the screen to your desk.

Produced by the WebPulse Newsroom with AI assistance from the original reporting credited below, and checked against that source by our editorial review. How we use AI.
Original reporting: Trezor (SatoshiLabs).