French cryptocurrency tax platform Waltio disclosed a data breach affecting approximately 50,000 users after hackers demanded ransom.
The Shiny Hunters group obtained customer emails and 2024 tax report data in the attack.
Waltio CEO Pierre Morizot said Friday the breach occurred January 21 through what the company described as a "particularly sophisticated attack." The platform provides portfolio tracking and tax calculation services for cryptocurrency holders.
The Paris Public Prosecutor's cybercrime division is investigating the incident. Waltio filed complaints for attempted extortion and unauthorized access to automated data processing systems.
What Was Compromised
Hackers obtained user email addresses and capital gains and losses from 2024 tax reports, according to French newspaper Le Parisien. The company said passwords and other sensitive credentials were not accessed.
Morizot warned the primary risk involves social engineering attacks. Cybercriminals could use tax report details to impersonate authorities or the platform itself when targeting victims.
"Some attackers may use contextual elements to appear credible," Morizot said in a statement.
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Why Physical Attacks Matter
France has experienced multiple violent "wrench attacks" targeting cryptocurrency holders. Criminals use stolen personal data to identify and physically threaten victims into transferring digital assets.
Four attempted kidnappings occurred within four days in early January across France. Such attacks typically involve armed intruders forcing victims to surrender cryptocurrency access codes under threat of violence.
The Waltio breach provides criminals with verified information identifying French residents who hold taxable cryptocurrency positions. Tax compliance data creates particularly high-value targets compared to typical exchange breaches.
Shiny Hunters members were previously arrested in France but the group continues operations under the same name.
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