Bithumb Discloses Data Leak After Internal System Hack

Bithumb, South Korea's second-largest crypto exchange, disclosed a data leak resulting from a hack of its internal mobile system used by employees. The company stated that an unauthorized outside party accessed its internal mobile groupware system, leading to the leak of personal information. Bithumb discovered the breach on Tuesday and notified the Korea Internet & Security Agency and the Personal Information Protection Commission that same day. The exchange is currently investigating whether member data was compromised during the incident. An industry source told Yonhap that some personal information belonging to Bithumb customers had been leaked. Bithumb has not explained how its system was accessed by the attackers.

The company emphasized that customer virtual assets cannot be accessed through this breach because the internal work system is separated from the trading system. This incident is part of a broader wave of cyberattacks affecting the South Korean financial sector. South Korea's Financial Supervisory Authority reported that cyberattacks had hit 16 South Korean financial firms as of October 14. Bithumb was one of three South Korean financial firms to report data breaches on Wednesday. Daishin Securities also reported that personal and credit information belonging to 38,490 customers had been leaked. Security researchers linked a September wave of attacks on South Korea to a suspected China-based hacker who relied on an AI penetration testing tool called Artex.

This breach represents the latest setback for Bithumb in 2026. In February, the exchange mistakenly credited users with 620,000 BTC. In March, South Korea's Financial Intelligence Unit fined Bithumb 36.8 billion won, equivalent to $24.6 million, over anti-money laundering failures. Additionally, Bithumb's CEO, Lee Jae-won, was booked as a bribery suspect in June over the alleged hiring of a National Assembly member's son. Despite these challenges, Bithumb has set out a three-stage plan to list on the stock market in 2028.

South Korea's Financial Services Commission, Daishin Securities, Bithumb, and Mirae Asset Global Investments did not immediately respond to requests for comment regarding the recent incidents.