Coinone Warns of Phishing and Identity Theft After Customer Service Breach

South Korean cryptocurrency exchange Coinone warned customers of potential identity theft and phishing risks after an intruder breached its third-party customer support provider ¹. The incident occurred when an attacker accessed systems run by MetaM, an outsourced support vendor, compromising customer service records viewed or extracted during support inquiries ¹. Coinone stated it discovered the intrusion on the same day the servers were breached ¹.

According to Coinone, the exposed information includes full names, dates of birth, phone numbers, email addresses, national identification numbers, bank account numbers, residential addresses, crypto wallet addresses, transaction IDs, and passwords shared during support interactions ¹. The exchange noted that the specific records exposed vary by individual, and users who never contacted customer service were not impacted ¹. Coinone did not reveal the total number of affected users ¹. Users who submitted credentials during previous support sessions were urged to change them, as bad actors could deploy the stolen records for targeted phishing scams ¹.

Exchange Infrastructure Intact Amid Regulatory Push

Coinone clarified that its internal trading, account, and custody wallet infrastructure remains uncompromised, as these core systems operate independently from MetaM's external servers ¹. The platform confirmed it reported the security incident to South Korean law enforcement and regulatory authorities ¹. Similar supply-chain vulnerabilities have previously affected major trading platforms, such as when a Coinbase vendor breach exposed select user information while core funds remained isolated.

The disclosure aligns with increased regulatory scrutiny across South Korea's financial ecosystem ¹. In October, the Financial Services Commission (FSC) reported security deficiencies across 130 of 555 evaluated financial institutions ¹. Days before the Coinone disclosure, the FSC announced rules permitting digital asset exchanges to halt withdrawals upon suspecting a hack, while requiring continuous, 24-hour network monitoring ¹. At the time of writing, broader market sentiment remains constrained, with $BTC trading at $64,535 and $ETH at $1,796 amid extreme market fear.