South Korean cryptocurrency exchange Bithumb said an outsider breached an internal mobile system used by employees and stole personal information, while the company continues to assess whether customer data was involved. The exchange said no cryptocurrency funds had been reported missing as of Wednesday afternoon in Asia.
Internal system breach under investigation
Bithumb discovered the intrusion on Tuesday and said the affected system is used by employees for work and internal messaging. The company described it as separate from its trading platform, meaning the breach did not provide access to customer virtual assets through the exchange’s trading infrastructure.
The exchange reported the incident to the Korea Internet & Security Agency and the Personal Information Protection Commission, according to Korean media. Bithumb told Yonhap that it was examining the full scope of the incident, including whether information belonging to its members had been exposed.
The company has not disclosed how many people may have been affected. It also has not said whether deposits or withdrawals were interrupted. The available information therefore confirms the theft of personal information from the employee system, but does not establish the scale of any customer-data exposure.
Bithumb is South Korea’s second-largest cryptocurrency exchange by trading volume. Its statement that the compromised system is separate from the trading platform distinguishes the reported data breach from a direct compromise of the exchange’s crypto-asset custody or transaction systems. No crypto funds were reported lost at the time covered by the report.
Part of wider attacks on South Korean finance
The incident emerged as South Korean authorities were reviewing cyberattacks involving financial companies. The Financial Supervisory Service said on Wednesday that Bithumb was one of three financial firms it was assessing.
Daishin Securities said an external attack exposed personal and credit information belonging to 38,490 customers. Mirae Asset Global Investments said it had blocked abnormal access to some of its web systems and that investor information was not affected.
Financial Supervisory Service Governor Lee Chan-jin told a meeting with bank holding-company chairs that he understood major financial investment companies had experienced hacking incidents the previous day. Earlier in October, he said cyberattacks had affected 16 South Korean financial firms as of October 14.
The sequence places Bithumb’s breach within a broader examination of cybersecurity at financial institutions. The details differ among the companies: Bithumb reported stolen personal information and an ongoing review of possible member-data involvement, while Mirae Asset said investor information was not affected. The reports from the three firms do not, on the information available, indicate that customer cryptocurrency balances were taken from Bithumb.
Bithumb had already faced a controls failure this year
The reported intrusion is the second major challenge to Bithumb’s internal controls mentioned in the source material this year. In February, the exchange mistakenly credited customers with 620,000 bitcoin rather than 620,000 won. The bitcoin amount was valued at more than $40 billion at the time.
Chief Executive Lee Jae-won attributed that episode to weak internal controls and said the exchange was acutely aware of the deficiency in its internal system control. That earlier incident involved an erroneous customer credit, whereas the latest event concerns an outsider’s access to an employee system and the theft of personal information.
Bithumb’s current investigation will determine whether the latest breach extended beyond the employee environment. Until the company provides further details, key unanswered questions include the number of affected individuals, whether any member information was exposed, and whether the incident had any effect on deposits or withdrawals.
Market picture
Moneyiar market data at the given time, October 25, 2026, showed Ethereum at $2,342.0570017305, up 0.02% over 24 hours but down 1.77% over seven days. Other tracked assets were mixed over the day and lower over the week:
- Four (FORM): $0.2210079715, up 0.66% in 24 hours and down 7.29% over seven days.
- Berachain (BERA): $0.1518511758, down 0.9% in 24 hours and 9.55% over seven days.
- Alchemy Pay (ACH): $0.0050519273, down 2.05% in 24 hours and 2.83% over seven days.
The Ethereum figure was recorded at 22:39 on October 25, 2026, in the supplied Moneyiar data. Four and Alchemy Pay were also recorded at 22:39, while Berachain was recorded at 22:38. These market figures provide a snapshot of selected crypto assets and do not indicate the outcome of Bithumb’s security investigation.
