South Korean crypto exchange Coinone warned customers of potential phishing scams and identity theft after an attacker breached its outsourced customer support provider, exposing information shared during customer service interactions.
On Sunday, Coinone said an attacker accessed servers operated by MetaM on Thursday and viewed or extracted customer support records. Coinone said it learned about the breach in the same day.
According to Coinone, the information potentially exposed names, phone numbers, email addresses, dates of birth, bank account numbers, passwords, national identification numbers, home and wallet addresses and transaction IDs.
Coinone said the affected data varies by customer, and people who never contacted its support center were unaffected. It did not disclose how many customers were affected.
The exchange urged customers who shared passwords during support interactions to change them and warned that fraudsters could impersonate Coinone using details from previous conversations.
Coinone said its account, trading and wallet infrastructure operates separately from MetaM’s servers, with no evidence of direct compromise. The exchange said it has reported the incident to South Korean authorities.
The disclosure comes as South Korea moves to strengthen financial-sector cybersecurity. In October, the Financial Services Commission identified security deficiencies at 130 of 555 financial firms reviewed.
On Thursday, the regulator said it would allow crypto exchanges to suspend withdrawals when hacking is suspected, alongside calls for round-the-clock monitoring.
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