South Korea’s second-largest cryptocurrency exchange, Bithumb, is investigating an alleged breach of its internal mobile groupware system, which employees use for communication and work-related activities, according to Yonhap News. The incident occurred on October 28, when an outsider reportedly accessed the system. Personal information was reportedly taken, although the exchange is still determining whether customer data was included.
Bithumb emphasized that the compromised system operates separately from its trading platform, meaning the breach did not provide direct access to customers’ crypto assets. No cryptocurrency losses have been reported so far.
Other South Korean firms affected
The Bithumb incident coincides with attacks on other South Korean financial companies. Asset manager Mirae Asset Global Investments and brokerage firm Daishin Securities were also among the affected companies. Daishin Securities disclosed that personal and credit information belonging to 38,490 customers had been leaked in an external attack. The company reportedly implemented emergency measures soon after the revelation, and South Korea’s Financial Supervisory Service (FSS) began assessing the incidents and sent an on-site inspection team to Daishin Securities.
Mirae Asset said it detected and blocked abnormal access to some web systems and that investor information had not been affected. The differing disclosures left each firm facing the task of establishing what attackers accessed and whose information was exposed.
Wider security concerns
Earlier in October, authorities reported attacks affecting 16 financial firms, including banks, with approximately 100,000 cases of data leaks reported so far. FSS Governor Lee Chan-jin warned, “As artificial intelligence (AI) is utilized as a means of hacking, security vulnerabilities will be easily detected, and simultaneous attacks will become commonplace.” He added, “Recognizing that IT security is a core function for protecting customers’ assets and information and for maintaining financial trust, I ask the Board of Directors to take the lead in enhancing IT security capabilities.”
For Bithumb, the breach also follows a major internal control failure in February, when the exchange mistakenly credited customers with 620,000 Bitcoin (BTC) instead of 620,000 Korean won. Although the latest incident has not been linked to cryptocurrency theft, it raises fresh questions about the exchange’s internal safeguards. This also follows reports that South Korea has blocked 27 unregistered cryptocurrency exchange websites, including KuCoin, MEXC, and BingX, after earlier restrictions on mobile apps.
Coinbase clarifies third-party incident
Separately, Coinbase was in the spotlight after hackers allegedly accessed contact information belonging to more than 70,000 Coinbase users. However, Coinbase clarified that its own systems were not breached. Instead, Amplitude, a third-party analytics provider used by Coinbase, experienced a security incident that exposed some Coinbase customers’ contact information. Coinbase stated, “We’ve found no evidence of unauthorized access to Coinbase systems, and customer funds were not impacted.”
