A About 570,000 accountsA third party accessed the member information server via the Seicomart App server without authorization, and names, addresses, phone numbers and other data of about 570,000 accounts may have been viewed. Passwords and purchase history are stated not to have been leaked.
Unauthorized access & data leakPossibleOfficial statement
A 177,426 peopleIn operating the "insurance premium deduction certificate issuing service" that it runs for non-life insurers belonging to the General Insurance Association of Japan, TOPPAN on September 1, 2026 mistakenly placed a ZIP file containing Sompo Japan policyholder data inside a ZIP file for another non-life insurer and sent it. The cause was a manual drag-and-drop error and a failure to check the contents before sending. 177,426 policyholders are affected (the figure may include duplicates): names in katakana, policy numbers for premium deduction and business IDs. Addresses, dates of birth, phone numbers, credit card and bank account details are not included. The recipient discarded and completely deleted the data, and no leak to a third party has been confirmed. TOPPAN says the incident was not caused by unauthorized access or a cyberattack.
C 1,463 recordsThe system managing refund information for the e-ticket service "Smachike" was accessed without authorization on September 11-12, and email addresses, names, bank transfer account details and similar data of 1,463 customers who had applied for refunds were leaked. Credit card information was not included.
Unauthorized access & data leakConfirmedOfficial statement
E 19 peopleThe Yubinkyoku App was accessed without authorization from outside, and customer information of 19 people (69 items), including Yu-ID member information, address books and shipping label data, was improperly obtained. Emergency maintenance was carried out on September 25 and service resumed on September 26.
Unauthorized access & data leakConfirmedOfficial statement
The campaign system of the LINE official account was accessed without authorization, and LINE display names and campaign winning information of some users may have been viewed or leaked. Affected people and scope are under investigation.
Unauthorized access & data leakPossibleOfficial statement
