Credit card loan amount for 320,000 people leaked - Sumitomo Mitsui consumer finance giant

SMBC Consumer Finance (CF, formerly Promise), a major consumer finance company under the Sumitomo Mitsui Financial Group (FG), announced on the 5th that its system used for card loan guarantee operations had been accessed illegally, resulting in the leak of customer information for up to 320,118 people. In addition to customers' names and annual incomes, loan amounts were also leaked.

What was leaked was information about SMBCCF's customers at local banks, credit unions, online banks, and other institutions that provide guarantee services for card loans. In addition to the name, gender, date of birth, address, telephone number, email address, driver's license number, workplace, annual income, etc. of the person borrowing money, information such as the code of the financial institution from which the loan was taken, customer number, guarantee amount (loan amount), and contract date were leaked. On the same day, Docomo SMTB Net Bank (formerly Sumishin SBI Net Bank) announced that up to 122,635 people are its customers.

Unauthorized access was detected on the 2nd, and access to the system used for warranty work was blocked. However, some data was sent externally, including customer information. As of now, no misuse of the leaked information has been confirmed.

As of March 2026, SMBCCF has contracted guarantee services from 189 financial institutions.