Do not use any crypto tax software that only accepts card payments.

The French cryptocurrency tax platform Waltio suffered a data breach affecting approximately 50,000 users. Perpetrated by the Shiny Hunters hacking group, the January 2026 incident involved an extortion attempt after hackers exfiltrated user email addresses, payment details, and tax report data.

A crypto tax software data breach is so much worse than an exchange or hardware wallet data breach because it ties your identity and home address directly to your self-custody public addresses and total crypto net worth.

If a crypto tax platform only accepts card payments the payment gateway requires your full name and billing address to process the payment. That identity data is then tied directly to your profile. If a data breach occurs all of that information is then exposed to the dark web making you a target for physical attacks.

You can use crypto tax software without a name and while using an anonymous email, but never use crypto tax software that only accepts card payments because that card payment ties your identity and home address directly to your public addresses and net worth data.

If a crypto tax platform only accepts card payments consider this a massive red flag.

Crypto tax platforms have a responsibility to protect your identity, and the only way to guarantee this is to allow completely anonymous accounts. They have an obligation to accept anonymous payment methods and if they do not do this then do not use them.