Search incidents by company, country, industry, year and attack method. Review affected data, impact, verification status, company responses and sources.
The Bank of Yokohama announced on November 5 that SMBC Consumer Finance, guarantor of its card loan and free loan, reported that a guarantee-system intrusion leaked the bank's customer data.
Gakken Holdings announced a first report on November 5 after being told that unauthorised access to Arara, which handles group email delivery, leaked some customer personal data.
Tsukuba Bank announced on November 5 that SMBC Consumer Finance, guarantor for some of its card loans, reported a guarantee-system intrusion that also affected the bank's customers.
NTT DOCOMO confirmed customer-data exposure after unauthorized access to the two services, describing the scale as at most approximately 300,000 records.
SMBC Consumer Finance confirmed that a system used for loan-guarantee work with partner banks was accessed without authorisation and that data sent externally contained customer personal data.
GMO Payment Service was told that customer data leaked via Arara Message, used by contractor law firm Martial Arts for emails.
Ogaki Kyoritsu Bank announced on November 5 that SMBC Consumer Finance, a card-loan partner, reported that some applicant data the bank had supplied leaked in a system intrusion.
On November 4, 2026, Euglena confirmed unauthorised access to the akyrise cosmetics e-commerce site, and purchasers' member data was found to have leaked.
Ehime Bank announced on November 5 that SMBC Consumer Finance, guarantor for some of its card loans, reported a guarantee-system intrusion that also affected the bank's customers.
AIRDO was informed that unauthorised access to an external email-delivery system it uses leaked the recipient addresses of emails sent through it.
Kakaku.com was told that unauthorised access to Arara, its email-delivery contractor, leaked email addresses of users of Tabelog, Kakaku.com, Suumo-related Sumaity, Kyujinbox and icotto, and announced it on November 5.
NTT Townpage was told that some newsletter addresses leaked in the breach of Arara's repica, used by its contractor.
Asahi Mutual Life announced on November 5 that unauthorised access to the Arara email system used by its email contractor leaked customer email addresses.
Yokote City announced on November 5 that ransomware against contractor Shibata Survey (Yuzawa) may have leaked addresses and names of landowners handled in city-commissioned survey work.
Nissan FS said personal data related to its outsourced road-service work may have been taken in the intrusion into PremierNet2, the system of contractor Prestige Core Solutions (PCS).
Dentsu reported potential exposure following an incident at its service provider.
Sumitomo Realty learned on November 2 that housing-inquiry email addresses leaked through the Arara service used by its contractor Data X.
Unauthorised access to the Kikan Navi investor-relations service led to downloaded data including about 2,000 investor/analyst records and about 250 former-employee records.
Duskin was told on November 2 that unauthorised access to Arara, provider of the repica service used for DDuet emails, leaked member email addresses.
Solaseed Air announced on November 4 that unauthorised access to an external email system it uses led to downloaded files containing customer email addresses.