South Korean cryptocurrency exchange Coinone has alerted its customers to potential phishing scams and identity theft following a data breach at its outsourced customer support provider, MetaM. The breach occurred on Thursday, November 12, 2026, when an attacker accessed servers operated by MetaM and viewed or extracted customer support records. Coinone learned about the incident the same day.
The exposed information varies by customer but may include names, phone numbers, email addresses, dates of birth, bank account numbers, passwords, national identification numbers, home and wallet addresses, and transaction IDs. Customers who never contacted the support center were unaffected. Coinone did not disclose the number of affected users.
The exchange urged customers who shared passwords during support interactions to change them immediately. It also warned that fraudsters could impersonate Coinone using details from previous conversations. Coinone emphasized that its account, trading, and wallet infrastructure operates separately from MetaM’s servers, with no evidence of direct compromise. The exchange has reported the incident to South Korean authorities.
The disclosure comes as South Korea intensifies efforts to strengthen financial-sector cybersecurity. In October 2026, the Financial Services Commission identified security deficiencies at 130 of 555 financial firms reviewed. On Thursday, the regulator announced that crypto exchanges can suspend withdrawals when hacking is suspected, alongside calls for round-the-clock monitoring.