2026 Bithumb — unauthorised access to internal mobile groupware; employee data reported leaked, customer data under review
Data compromised
Employee personal information, which press reports say was leaked. Customer data is under investigation. Press reports give conflicting customer counts (844 and 6,444), none confirmed by Bithumb.
Technical writeup
Bithumb's own announcement was not reviewed directly. The October 27 discovery date is inferred from press reports. Reported counts conflict and are not used in recordsAffected.
Root cause
Bithumb says an outside party gained unauthorised access to its internal mobile groupware, the platform staff use for internal communication. The company says it is analysing the exact scope, including whether member information was involved. It says customer assets were not affected.