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200 results
Disclosed 2026-08-06Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Ambition DX Holdings: ransomware attack[Ransomware][Intrusion][Data leak]Leaked 580KOrganizations 1Disclosed 2026-08-05Updated 2026-10-22Tokyo[Investigating][Severity: Major]
Kyodo News: staff accounts misused[Credential abuse][Data leak]Leaked 6KOrganizations 1Disclosed 2026-08-04Updated 2026-10-22Tokyo[Contained][Severity: Major]
Innovation: unauthorized access to its GitHub[Credential abuse][Data leak]Leaked 62.7KOrganizations 1Disclosed 2026-08-03Updated 2026-10-22Tokyo[Contained][Severity: Major]
Kodansha: unauthorized access to a company email account[Phishing][Credential abuse][Data leak]Leaked 3.8KOrganizations 1Disclosed 2026-08-01Updated 2026-10-22Ishikawa, Tokyo[Contained][Severity: Critical]
Estore: shopper data leaked from ShopServe[Web app exploit][Data leak]Leaked 23.4MOrganizations 2Disclosed 2026-07-31Updated 2026-10-23Tokyo[Contained][Severity: Critical]
EPARK Relax & Esthe: unauthorized access to the PeakManager booking system[Credential abuse][Data leak]Leaked 33MOrganizations 1Disclosed 2026-07-29Updated 2026-10-23Tokyo[Contained][Severity: Major]
Life Insurance Association: user data viewable in the policy inquiry system[Misconfiguration][Data leak][Service outage]Leaked 37.9KOrganizations 1Disclosed 2026-07-24Updated 2026-10-22Tokyo[Contained][Severity: Critical]
murauchi.com: unauthorized access[Web app exploit][Data leak][Service outage]Leaked 7.7MOrganizations 1Disclosed 2026-07-16Updated 2026-10-23Tokyo[Resolved][Severity: Moderate]
Nissan Chemical: unauthorized logins to its cloud environment[Credential abuse]Organizations 1Disclosed 2026-07-14Updated 2026-10-23Tokyo[Contained][Severity: Major]
Media4u: unauthorized access to its SMS delivery system[Web app exploit][Data leak]Leaked 95.4KOrganizations 1Disclosed 2026-07-13Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Nichirei: cyberattack[Intrusion][Data leak][Service outage]Leaked 43.7KOrganizations 1Disclosed 2026-07-13Updated 2026-10-22Tokyo[Investigating][Severity: Critical]
Nihon Kotsu: malware attack[Malware][Data leak][Service outage]Organizations 1Disclosed 2026-07-01Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Kaga Solution Network: unauthorized access to the Academico Navi student PC store[Web app exploit][Data leak][Service outage]Leaked 170KOrganizations 3Disclosed 2026-06-30Updated 2026-10-23Tokyo[Investigating][Severity: Major]
Musashino University: ransomware; files in shared folders were taken[Ransomware][Service outage][Data leak]Organizations 1Disclosed 2026-06-30Updated 2026-10-22Tokyo[Contained][Severity: Critical]
Aflac Life Insurance Japan: unauthorized access to online systems[Web app exploit][Data leak][Service outage]Leaked 4.4MOrganizations 1Disclosed 2026-06-23Updated 2026-10-22Aichi, Kagawa, Tokyo[Contained][Severity: Critical]
KDDI: unauthorized access to its mail system for ISPs[Intrusion][Data leak]Leaked 12.2MOrganizations 7Disclosed 2026-06-22Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
Hands Holdings: ransomware attack[Ransomware][Data leak][Service outage]Organizations 1Disclosed 2026-06-19Updated 2026-10-23Osaka, Tokyo[Contained][Severity: Critical]
Delightful: unauthorized access to the Meruhaikun email delivery system[Web app exploit][Intrusion][Data leak][Service outage]Leaked 1.7MOrganizations 4Disclosed 2026-06-16Updated 2026-10-22Tokyo[Resolved][Severity: Critical]
Komatsu: misconfigured external user directory[Misconfiguration][Data leak]Leaked 139.3KOrganizations 1Disclosed 2026-06-15Updated 2026-10-23Tokyo[Investigating][Severity: Moderate]
Factory Japan Group: unauthorized access to its servers[Intrusion]Organizations 1Disclosed 2026-06-12Updated 2026-10-22Tokyo[Contained][Severity: Major]
D&M: ransomware attack[Ransomware][Data leak]Leaked 633Organizations 1Disclosed 2026-06-10Updated 2026-10-22Tokyo[Contained][Severity: Critical]
Kaizen Tech Agent: suspected data theft by a former employee[Insider][Data leak]Leaked 9.7KOrganizations 1Disclosed 2026-06-05Updated 2026-10-22Tokyo[Contained][Severity: Major]
en: credential stuffing attack on the Middle no Tenshoku job site[Credential abuse][Data leak]Leaked 2.5KOrganizations 1Disclosed 2026-06-05Updated 2026-10-22Tokyo[Contained][Severity: Critical]
Sen: unauthorized access to Hai Cheese! Photo[Web app exploit][Data leak][Service outage]Organizations 1Disclosed 2026-05-28Updated 2026-10-22Tokyo[Contained][Severity: Major]
Asoview: unauthorized access to the satsuki booking system[Intrusion][Data leak]Leaked 27.2KOrganizations 1Disclosed 2026-05-28Updated 2026-10-22Tokyo[Investigating][Severity: Critical]
Polaris Holdings: unauthorized access to its Booking.com account[Credential abuse][Fraud][Financial loss]Organizations 1Disclosed 2026-05-21Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Geniee: unauthorized access to GENIEE MA[Credential abuse][Financial loss]Organizations 1Disclosed 2026-05-15Updated 2026-10-23Tokyo[Resolved][Severity: Moderate]
CS Accounting: unauthorized access to its servers[Credential abuse]Organizations 1Disclosed 2026-05-14Updated 2026-10-22Tokyo[Contained][Severity: Major]
Nihon Shisan Souken: ransomware attack[Ransomware][Credential abuse][Data leak][Service outage][Extortion]Organizations 1Disclosed 2026-05-12Updated 2026-10-22Tokyo[Investigating][Severity: Major]
Oriental Diamond: ransomware attack[Ransomware][Data leak][Service outage]Organizations 1Disclosed 2026-05-12Updated 2026-10-22Tokyo[Contained][Severity: Critical]
Tokyo Hoso Kogyo: ransomware attack[Ransomware][Data leak]Organizations 1Disclosed 2026-05-09Updated 2026-10-22Tokyo[Contained][Severity: Critical]
Matsuzawa Shoten: ransomware attack[Ransomware][Service outage]Organizations 1Disclosed 2026-05-07Updated 2026-10-22Tokyo[Contained][Severity: Major]
East: unauthorized access to its internal network[Intrusion][Data leak]Organizations 1Disclosed 2026-05-01Updated 2026-10-22Tokyo[Contained][Severity: Major]
Money Forward: unauthorized access to its GitHub[Credential abuse][Data leak]Leaked 60.4KOrganizations 1Disclosed 2026-04-23Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Yellow Hat: member data taken through the 2Rinkan app API[API abuse][Data leak][Service outage]Leaked 3.5MOrganizations 1Disclosed 2026-04-10Updated 2026-10-23Tokyo[Contained][Severity: Moderate]
UPSIDER: supply chain attack through open source software[Malware][Service outage]Organizations 1Disclosed 2026-04-09Updated 2026-10-22Tokyo[Contained][Severity: Major]
NYK: unauthorized access to the marine fuel procurement system[Intrusion][Data leak][Service outage]Organizations 1Disclosed 2026-04-08Updated 2026-10-22Tokyo[Investigating][Severity: Major]
ielove GROUP: unauthorized access to the ielove CLOUD real estate service[Credential abuse][Web app exploit][Data leak]Organizations 1Disclosed 2026-04-03Updated 2026-10-23Kanagawa, Tokyo[Contained][Severity: Critical]
CAMPFIRE: unauthorized access to its GitHub account[Credential abuse][Data leak]Leaked 225.8KOrganizations 2Disclosed 2026-03-24Updated 2026-10-23Tokyo[Contained][Severity: Major]
Cynd: unauthorized access to the BeautyMerit booking system[Unknown][Data leak]Organizations 1Disclosed 2026-03-06Updated 2026-10-24 03:51Kanagawa, Tokyo[Resolved][Severity: Moderate]
Seed Planning: ransomware attack[Ransomware][Service outage]Leaked 130KOrganizations 4Disclosed 2026-02-19Updated 2026-10-26 18:29Tokyo[Contained][Severity: Major]
Advantest: ransomware attack[Ransomware][Intrusion][Data leak][Service outage]Organizations 1Disclosed 2026-02-13Updated 2026-10-23Tokyo[Contained][Severity: Critical]
BEENOS: unauthorized access to the Sekaimon overseas shopping service[Web app exploit][Data leak][Service outage]Organizations 1Disclosed 2026-02-12Updated 2026-10-23Tokyo[Resolved][Severity: Major]
Ficha: ransomware attack on its servers[Ransomware][Data leak]Organizations 1Disclosed 2026-02-12Updated 2026-10-23Tokyo[Contained][Severity: Major]
Mynavi: unauthorized access to a cloud service it uses[Unknown][Data leak]Leaked 74.2KOrganizations 1Disclosed 2026-02-05Updated 2026-10-23Tokyo[Contained][Severity: Critical]
At Home: unauthorized login to the moving quote system[Credential abuse][Data leak][Service outage]Leaked 5.1KOrganizations 1Disclosed 2026-01-22Updated 2026-10-23Tokyo[Contained][Severity: Major]
Sincere: ransomware attack[Ransomware][Service outage][Data leak]Organizations 1Disclosed 2026-01-06Updated 2026-10-22Tokyo[Resolved][Severity: Major]
CANVASs: ransomware attack on its licensing server[Ransomware][Service outage]Organizations 1Disclosed 2026-01-06Updated 2026-10-22Tokyo[Investigating][Severity: Moderate]
Mizuho Leasing: unauthorized access to a power investment system[Unknown]Organizations 1Disclosed 2026-01-05Updated 2026-10-23Tokyo[Resolved][Severity: Major]
CAC: unauthorized access to the Academic Support Navi donation service[Credential abuse][Malware][Service outage]Organizations 1