France Tax Data Leak Deepens Crypto Security Risk

France's latest tax-data breach creates a security problem for cryptocurrency holders that cold storage cannot solve. The French tax authority confirmed August 14 that attackers extracted data on 678,000 individuals and businesses, including income and property information. Separately, security firm CertiK recorded 33 verified physical crypto attacks in France during the first half of 2026, making the country the largest concentration in its global dataset.

The breach does not directly expose crypto wallets. The combination of identity, income and address data with a rising trend in wrench attacks expands the threat surface. French prosecutors said in March a family in Vaires-sur-Marne was targeted by mistake when attackers searched for cryptocurrency. A couple in Le Chesnay was forced to transfer about €900,000 in Bitcoin.

The DGFiP detected the intrusion in June and July after a malicious actor compromised credentials of a tax official and an authorized third party. The affected access was terminated. The attacker later publicly claimed data extraction, which subsequent investigations confirmed. The government said 678,000 individuals and professionals were affected. Online tax accounts were not compromised.

CertiK recorded 52 verified wrench attacks globally during the first half of 2026, up from 39 in the same period of 2025. France accounted for 33 cases. The financial exposure associated with the worldwide attacks reached approximately $124.1 million, compared with $10.5 million a year earlier. Home invasions rose from one verified incident in the first half of 2025 to 20 in H1 2026.