In Untersuchung
Zetton’s forty three reports possible leak of 18,553 personal-data records
Unauthorised access to two legacy-mail accounts may have exposed 18,553 personal-data records. The two accounts are not a count of affected people.
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In Untersuchung
Joyfull: data of 23,585 employees/applicants and relatives may have leaked via contractor Zynas cyber-attack
Contractor Zynas confirmed unauthorised access to a subcontractor hand-off server on January 29, 2026; its March 26 notice says Joyfull employee/applicant/relative data may be in scope (Joyfull’s own PDF returned HTTP404 at collection time, so the contractor official notice is cited).
In Untersuchung
MoonStar: server intrusion may have exposed online-store customer data for up to about 593,000 people
Possible data leak: First notice Mar 26, 2026 reported suspected server intrusion (no confirmed theft then). Oct 2/15 follow-ups concluded name/address/phone/email/order data likely leaked May 14–19 for up to 593,000 online-store customers. Cards/passwords not stored. First disclosure remains Mar 26.
In Untersuchung
Sato Kogyo: worker and emergency-contact data may have been viewed after jobsite NAS intrusion
Unauthorised access to one jobsite NAS was confirmed on November 5, 2025; Sato disclosed on March 26, 2026 that personal data may have been viewed.
In Untersuchung
Niigata University Hospital: endocrine/metabolic patient data may have leaked after USB loss
Possible data leak: A USB used in an in-hospital meeting on November 5, 2025 was found missing on November 18; disclosed March 25, 2026.
Bestätigt
Osaka Marathon Organising Committee: volunteer system auth disabled, exposing 4,101 registrants
Before shutdown work a contractor disabled personal authentication so other volunteers could view data from March 16–18, 2026; Osaka Prefecture and Osaka City disclosed on March 25.
Bestätigt
Niigata University: student/guarantor roster of 1,478 people misattached to degree-check mail
The Graduate School of Science and Technology misattached an Excel sheet with roster data for 1,478 enrolled students to a degree-content check mail; disclosed March 24, 2026.
Bestätigt
Fukushima University: faculty ages left reachable on the web via installation-plan reports
Faculty ages were left in installation-plan reports and pre-replacement CMS files remained searchable; disclosed March 24, 2026.
Bestätigt
NICT: voice files of 115 speakers leaked via mispublished speech corpus
A research speech corpus published on March 12, 2026 wrongly included 115 out-of-scope voice-check files found on March 13; disclosed March 19.
In Untersuchung
Mazda: 692 employee/partner records may have leaked after parts-warehouse system intrusion
In mid-December 2025 unauthorised access to a Thailand parts-warehouse system was found; Mazda disclosed possible personal-data exposure on March 19, 2026. Consumer customer data are stated not to be on that system.
In Untersuchung
Hotel Nikko Princess Kyoto: Expedia admin-account abuse may have exposed guest data and triggered fake payment messages
Possible data leak: On March 2, 2026 the hotel’s Expedia admin account was abused to send WhatsApp messages seeking card details; disclosed March 19.
Bestätigt
Sekibunkan: 320 customer emails leaked via misaddressed textbook-sales mail
On March 18, 2026 a textbook re-acceptance notice was sent so recipients could see one another’s addresses; apology published March 19.
Bestätigt
NHK: 32,940 information-system registrant emails leaked via misaddressed mail
On March 17, 2026 a vendor operator wrongly selected all information-system registrants for an approval mail so addresses were visible within each send group; NHK disclosed on March 18.
Bestätigt
International Budo University: personal data of about 120 graduates leaked via IT contractor intrusion
The IT contractor detected an intrusion in early November 2025 and reported on February 16, 2026 that some graduate data had leaked; the university disclosed on March 18.
In Untersuchung
Tane General Hospital: surgical-patient data of 379 people may have leaked after contractor USB loss
Possible data leak: A contractor SPD worker noticed a USB with surgical data missing on February 19, 2026; the hospital was told on February 20 and disclosed on March 17.
In Untersuchung
Medica Publishing: customer and related personal data may have leaked after ransomware
Possible data leak: Ransomware struck on March 13, 2026 (disclosed March 17). The May 13 investigation found no definitive exfiltration proof but could not rule it out, treating an approximate 641,000 people as at risk.
In Untersuchung
Nippon Telenet: entrusted and customer personal data may have leaked after ransomware
A cyber-attack disruption began March 9, 2026 (disclosed March 17). The June 12 update reported no detected outbound transfer but still listed category counts that may be at risk.
Bestätigt
United Arrows: partner-list personal data of about 10,000 people leaked after ex-employee removal
An employee who left at end-December 2025 removed partner lists via a cloud external-link feature; discovered in January 2026 and disclosed March 16.
In Untersuchung
Chukai TV: names and addresses may have leaked via misaddressed campaign direct mail
Possible data leak: A March 10, 2026 campaign DM had mismatched names and delivery addresses; disclosed March 13.
In Untersuchung
Urasoe City: data of about 9,100 students and guardians may have leaked after contractor HDD loss at Minatogawa JHS
Possible data leak: A contractor portable HDD used in Minatogawa Junior High file-server recovery was found missing on February 10, 2026; the city disclosed on March 13.