Crypto Security Now Extends Past The Wallet To The Customer's Address

What Happened

BeInCrypto spoke with experts from Hacken and Zama to uncover what a provider owes its customers when a supplier leaks their identity, which data the industry should stop keeping, and how a client could tell that a custodian will fail them under coercion.

When Trezor announced the breach in August, it made a point of what had not happened. Its own systems were not compromised, it said, and its devices were secure.

However, Hacken’s Head of GRC and Security Operations, Dmytro Yasmanovych, explained that the absence of a stolen private key does not mean customers are out of danger.

Market Context

A French family was tied up for hours by attackers after their crypto. Police have not said how the attackers chose the house, and that gap is where the industry’s data problem lives.

At around 4 a.m. on September 20, four hooded men forced their way into a family home in northern France. They bound the parents and two children with black tape and forced the father to hand over his access codes and move 40,000 euros.

Why It Matters

Those assurances addressed the risk that hardware wallets exist to prevent: theft of funds.

Those attacks need a target, and the target may come from a record somebody kept. That makes data retention another security issue for the crypto industry.

Companies may need customer information for a specific transaction or service. However, keeping it indefinitely can create a separate risk if that information is later exposed. So which piece of customer information should the industry stop collecting, or delete sooner than it does?

Yasmanovych names the phone number. He explained that a company might need one to arrange a delivery, but that does not explain why it should remain in a customer database for years.

Details

The father is a salaried IT worker in the crypto industry. Prosecutors have not said yet how the attackers identified him.

A separate incident in the same month showed how easily that kind of information gets out. On August 13, hardware wallet maker Trezor told 13,689 customers that a breach at one of its shipping providers had exposed sensitive order data. The number grew to over 80,000.

Nothing links the two cases, and nothing needs to. Together, they describe the same exposure from both ends: a database that pairs a home address with proof of crypto ownership, and what happens when someone acts on that pairing.

What “No Keys Compromised” Leaves Out

“Someone who knows your name, home address, and that you own a hardware wallet has information they can use to target you. You can replace a compromised key in minutes. You cannot do the same with your home address.”

He argues that this is why the information held by delivery companies and other suppliers deserves as much attention as the wallet itself. If a database links a crypto holder to their home, the consequences can reach their family, too, Yasmanovych added.

“So a provider can prevent anyone from accessing your funds and still leave you exposed in a much more personal way. The question is whether its security measures protect the customer, not just the wallet.”

The French Numbers Behind the Warning

France shows what that looks like. Interior Minister Laurent Nuñez said in late June that authorities had recorded more than 70 crypto-related violent incidents since January.

Chainalysis, which counted publicly reported cases, logged 30 in France through mid-2026, compared with 19 for the whole of 2025.

The firm calls a data breach the likeliest cause. It points to a 2024 case in which a French tax official allegedly stole dossiers on high-net-worth crypto holders, including addresses and phone numbers, and sold them to criminal intermediaries.

The family exposure Yasmanovych describes is visible in the same data. In France, more than 40% of incidents targeted a relative rather than the holder. Overall, home invasions made up 37% of documented attacks by mid-2026, up from 26% in 2023.

Chainalysis estimated that violent attacks on holders worldwide took more than $30 million in the first half of the year. This counts only attacks where the holder gave up funds.

The report puts total exposure at $107 million, including ransom demands, blocked transfers, and recovered funds, while noting that even that figure covers only reported cases.

The Data Behind the Target