Find incidents
Cyberattacks and data leaks that hit organizations in Japan. Filter by disclosure date, method, impact and status, or by where the affected organizations are, their industry or type and size.
316 results
Disclosed 2026-10-27Updated 2026-10-27Tokyo[Contained][Severity: Major]
Hiroshima Gakuin Junior and Senior High School: Microsoft 365 account intrusion[Credential abuse][Phishing][Data leak]Organizations 1Disclosed 2026-10-27Updated 2026-10-27Tokyo[Investigating][Severity: Major]
JETRO: e-Venue intrusion[Web app exploit][Data leak][Service outage]Leaked 133Organizations 1Disclosed 2026-10-27Updated 2026-10-27Tokyo[Contained][Severity: Critical]
MICIN: curon online clinic credential stuffing[Credential abuse][Data leak]Organizations 1Disclosed 2026-10-27Updated 2026-10-27Tokyo[Contained][Severity: Major]
Smartshare: OWNLY intrusion[Web app exploit][Data leak]Leaked 14KOrganizations 2Disclosed 2026-10-26Updated 2026-11-02Hyogo, Tokyo[Investigating][Severity: Major]
Sonicmoov: COMSBI Enterprise breach leaks 5,529 UCC Ueshima Coffee customer email addresses[Credential abuse][Data leak][Service outage]Leaked 5.5KOrganizations 2Disclosed 2026-10-26Updated 2026-10-30Tokyo[Investigating][Severity: Major]
Yakult Honsha: website intrusion[Unknown][Data leak][Service outage]Leaked 40KOrganizations 1Disclosed 2026-10-26Updated 2026-10-28Tokyo[Investigating][Severity: Major]
Dear Care: external site system intrusion and tampering[Intrusion][Service outage]Organizations 1Disclosed 2026-10-26Updated 2026-10-28Tokyo[Investigating][Severity: Major]
Starks: Cloudlogi Metabase intrusion[Unknown][Data leak]Organizations 1Disclosed 2026-10-26Updated 2026-10-27Tokyo[Investigating][Severity: Critical]
Bandai Logipal: intrusion affecting Ichiban Kuji deliveries[Intrusion][Credential abuse][Data leak][Service outage]Organizations 2Disclosed 2026-10-26Updated 2026-10-27Tokyo[Contained][Severity: Critical]
Rakuten Group: Rakuten Travel booking-site intrusion[Intrusion][Data leak]Leaked 2.6MOrganizations 1Disclosed 2026-10-26Updated 2026-10-26Tokyo[Investigating][Severity: Critical]
Doutor Coffee: intrusion; possible employee data leak[Intrusion][Data leak]Leaked 951Organizations 1Disclosed 2026-10-26Updated 2026-10-26Tokyo[Resolved][Severity: Moderate]
FC Tokyo: website defacement[Web app exploit][Site defacement]Organizations 1Disclosed 2026-10-26Updated 2026-10-26Tokyo[Contained][Severity: Critical]
giftee: system intrusion and fraudulent e-gift issuance[Web app exploit][Fraud][Financial loss]Organizations 1Disclosed 2026-10-26Updated 2026-10-26Tokyo[Investigating][Severity: Major]
Gunosy: stolen work account used to access business tools[Credential abuse][Data leak]Leaked 132Organizations 1Disclosed 2026-10-26Updated 2026-10-26Tokyo[Investigating][Severity: Major]
JP Union: old mail magazine system intrusion[Intrusion][Data leak]Organizations 1Disclosed 2026-10-26Updated 2026-10-26Tokyo[Ongoing][Severity: Moderate]
Lawson: app pre-order store-search supplier intrusion[Unknown][Service outage]Organizations 1Disclosed 2026-10-26Updated 2026-10-26Tokyo[Contained][Severity: Major]
Tokuma Shoten Publishing: GoodsPress Web test intrusion[Intrusion][Data leak][Site defacement]Leaked 103Organizations 1Disclosed 2026-10-24Updated 2026-10-28Fukushima, Gunma, Kyoto, Niigata, Shizuoka, Tokyo[Investigating][Severity: Critical]
IGREKS: Y-Mail system intrusion[Intrusion][Credential abuse][Data leak][Service outage]Organizations 8Disclosed 2026-10-24Updated 2026-10-24Tokyo[Contained][Severity: Critical]
Chariloto: betting app intrusion[Web app exploit][Data leak][Service outage]Leaked 373Organizations 1Disclosed 2026-10-23Updated 2026-10-30 12:04Tokyo[Investigating][Severity: Critical]
Good Smile Company: Official Shop intrusion[Web app exploit][Data leak][Service outage]Organizations 1Disclosed 2026-10-23Updated 2026-10-30Osaka, Tokyo[Contained][Severity: Critical]
Lindt: online shop and app member data stolen from Future Shop[Web app exploit][Data leak][Service outage]Leaked 3.1MOrganizations 2Disclosed 2026-10-23Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Nihon Seirei: AI Lab 225 intrusion[Intrusion][Malware][Data leak]Leaked 19.6KOrganizations 1Disclosed 2026-10-23Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
Commerble: GALLERY·2 online shop intrusion[Credential abuse][Misconfiguration][Data leak][Service outage]Leaked 128KOrganizations 2Disclosed 2026-10-23Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
Green Monster: FX Navi API data theft[API abuse][Data leak]Leaked 6.2MOrganizations 1Disclosed 2026-10-23Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
NEXCO EAST: Doratora expressway information site intrusion[Intrusion][Data leak]Organizations 1Disclosed 2026-10-23Updated 2026-10-23Tokyo[Contained][Severity: Major]
Nippon Gas: My Nichigas sign-up system intrusion[API abuse][Data leak]Leaked 85Organizations 1Disclosed 2026-10-23Updated 2026-10-23Tokyo[Investigating][Severity: Major]
Travel Zip: TAITO Odekake Navi intrusion[Intrusion][Data leak]Leaked 5.5KOrganizations 2Disclosed 2026-10-23Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
Tokio Marine X: possible contract management system intrusion[Intrusion][Service outage]Organizations 1Disclosed 2026-10-23Updated 2026-10-23Tokyo[Investigating][Severity: Moderate]
Tokyo Waterworks Bureau: external hard drives lost[Lost device][Data leak]Leaked 1.9KOrganizations 1Disclosed 2026-10-23Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Treasure Factory: intrusion into its case management system for home pickup and moving[Web app exploit][Data leak][Service outage]Leaked 746.3KOrganizations 1Disclosed 2026-10-23Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Valuedesign: Value Card intrusion[Intrusion][Web app exploit][Data leak]Leaked 1.4MOrganizations 2Disclosed 2026-10-22Updated 2026-10-31Tokyo[Investigating][Severity: Critical]
Strategic Marketing: Tokumoni! admin system intrusion[Intrusion][Data leak][Service outage]Leaked 42.9KOrganizations 1Disclosed 2026-10-22Updated 2026-10-27Ehime, Tokyo[Investigating][Severity: Major]
Level Enter: AI.R-Scorer intrusion[Web app exploit][Data leak]Organizations 3Disclosed 2026-10-22Updated 2026-10-26Tokyo[Contained][Severity: Critical]
KOMOJU: unauthorized access to payment and CRM systems[Intrusion][Data leak][Service outage]Leaked 4.1KOrganizations 1Disclosed 2026-10-22Updated 2026-10-26Tokyo[Investigating][Severity: Critical]
VALTEC: intrusion; possible customer data leak[Web app exploit][Malware][Data leak][Service outage]Organizations 1Disclosed 2026-10-22Updated 2026-10-23Aichi, Tokyo[Investigating][Severity: Critical]
Spiral LOCAS: staff call-up system intrusion[Intrusion][Data leak]Organizations 2Disclosed 2026-10-22Updated 2026-10-22Tokyo[Investigating][Severity: Critical]
Goldenway Japan: FXTF credential theft through external VPS[Credential abuse][Data leak][Fraud]Organizations 1Disclosed 2026-10-22Updated 2026-10-22Tokyo[Investigating][Severity: Moderate]
Lintec: unauthorized access to some systems[Intrusion]Organizations 1Disclosed 2026-10-22Updated 2026-10-22Tokyo[Investigating][Severity: Major]
Net Protections: NP Atobarai intrusion[API abuse][Data leak]Leaked 28.9KOrganizations 1Disclosed 2026-10-22Updated 2026-10-22Tokyo[Contained][Severity: Moderate]
SmartNews: server flaw exploited, service halted[Web app exploit][Service outage]Organizations 1Disclosed 2026-10-22Updated 2026-10-22Tokyo[Contained][Severity: Major]
Speee: unauthorized logins to group partner dashboards[Credential abuse][Data leak]Leaked 3.8KOrganizations 2Disclosed 2026-10-22Updated 2026-10-22Tokyo[Investigating][Severity: Major]
TechnoHill: 1FEdu unauthorized logins[Intrusion][Data leak][Service outage]Leaked 595Organizations 2Disclosed 2026-10-21Updated 2026-11-02 16:16Tokyo[Investigating][Severity: Critical]
GMO Internet: Onamae.com Desktop Cloud intrusion[Intrusion][Malware][Data leak][Service outage][Fraud][Extortion][Financial loss]Organizations 5Disclosed 2026-10-21Updated 2026-10-30Aichi, Ehime, Fukuoka, Hiroshima, Hokkaido, Iwate, Kagawa, Kanagawa, Mie, Miyagi, Miyazaki, Nagano, Niigata, Osaka, Shizuoka, Tochigi, Tokyo, Toyama, Yamaguchi, Yamanashi[Investigating][Severity: Critical]
RAKUS Light Cloud: blastmail mail system intrusion[Intrusion][Data leak][Service outage]Organizations 345Disclosed 2026-10-21Updated 2026-10-26Aichi, Akita, Aomori, Chiba, Ehime, Fukui, Fukuoka, Fukushima, Gifu, Gunma, Hiroshima, Hokkaido, Hyogo, Ibaraki, Ishikawa, Iwate, Kagawa, Kagoshima, Kanagawa, Kochi, Kumamoto, Kyoto, Mie, Miyagi, Miyazaki, Nagano, Nagasaki, Nara, Niigata, Oita, Okayama, Okinawa, Osaka, Saga, Saitama, Shiga, Shimane, Shizuoka, Tochigi, Tokushima, Tokyo, Tottori, Toyama, Wakayama, Yamagata, Yamaguchi, Yamanashi[Ongoing][Severity: Moderate]
php2shell: critical flaws in PHP[Web app exploit][Service outage]Organizations 608Disclosed 2026-10-21Updated 2026-10-23Hiroshima, Mie, Tokyo[Investigating][Severity: Major]
Sankei Living Shimbun: server intrusion[Intrusion][Data leak][Service outage]Leaked 1.5KOrganizations 4Disclosed 2026-10-21Updated 2026-10-21 12:41Tokyo[Investigating][Severity: Critical]
Recruit: Carsensor.net / C-MATCH intrusion[Intrusion][Data leak][Service outage]Leaked 3.7MOrganizations 1Disclosed 2026-10-21Updated 2026-10-21Tokyo[Investigating][Severity: Major]
Digital Arts: cloud service operations intrusion[Credential abuse][Data leak]Organizations 1Disclosed 2026-10-21Updated 2026-10-21Tokyo[Investigating][Severity: Major]
JFE Chemical: intrusion into its IT environment[Intrusion][Data leak]Organizations 1Disclosed 2026-10-21Updated 2026-10-21Tokyo[Investigating][Severity: Critical]
Monitas: SQL injection attack on the Qzoo survey site[Web app exploit][Data leak][Service outage]Leaked 400KOrganizations 1