Find incidents
Filter by disclosure date, method, impact and status, or by where the affected organizations are, their industry or type and size.
574 results
Disclosed 2025-06-30Updated 2026-10-23Hyogo[Contained][Severity: Major]
Furuno Electric: server intrusion[Intrusion][Malware][Data leak]Leaked 8.5KOrganizations 1Disclosed 2025-06-20Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Fujisan Magazine Service: login abuse at Fujisan.co.jp; addresses may have been exposed[Intrusion][Credential abuse][Data leak]Leaked 2.5MOrganizations 1Disclosed 2025-06-20Updated 2026-10-23Tokyo[Contained][Severity: Major]
Gibraltar Life: data stolen from an MDM server[Intrusion][Data leak]Leaked 550Organizations 1Disclosed 2025-06-20Updated 2026-10-23Tokyo[Contained][Severity: Major]
Prudential Life: data stolen from an MDM server[Intrusion][Data leak]Leaked 11.9KOrganizations 1Disclosed 2025-06-18Updated 2026-10-23Hiroshima[Contained][Severity: Critical]
DAISO: Google Groups left publicly visible[Misconfiguration][Data leak]Leaked 4.6KOrganizations 1Disclosed 2025-06-11Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
SoftBank: customer data mishandled at contractor UF Japan[Insider][Misconfiguration][Data leak]Leaked 161.1KOrganizations 1Disclosed 2025-05-20Updated 2026-10-23Tokyo[Resolved][Severity: Moderate]
Resonac: ransomware attack[Ransomware][Service outage]Organizations 1Disclosed 2025-05-16Updated 2026-10-23Miyagi[Contained][Severity: Major]
Miyagi Gakuin: ransomware and data leakage[Ransomware][Service outage][Data leak]Leaked 30KOrganizations 1Disclosed 2025-05-15Updated 2026-10-23Kyoto[Contained][Severity: Critical]
Sanshodo: ransomware attack[Ransomware][Service outage]Organizations 1Disclosed 2025-05-14Updated 2026-10-23Kanagawa[Investigating][Severity: Moderate]
Arc System Works: data leakage[Intrusion][Data leak]Organizations 1Disclosed 2025-05-12Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Cool Japan Fund: server intrusion[Intrusion][Data leak]Leaked 1.1KOrganizations 1Disclosed 2025-05-08Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Skylark: takeaway site intrusion[Web app exploit][Data leak][Service outage]Leaked 2.3KOrganizations 1Disclosed 2025-05-07Updated 2026-10-23Tokyo[Contained][Severity: Critical]
PR TIMES: admin system intrusion; data may have leaked[Intrusion][Credential abuse][Data leak]Leaked 901.6KOrganizations 1,182Disclosed 2025-05-01Updated 2026-10-23Kanagawa, Tokyo[Resolved][Severity: Major]
Gion: ransomware in its document management system[Ransomware][Data leak][Service outage]Leaked 75KOrganizations 2Disclosed 2025-04-25Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Sompo Japan: web system intrusion; data may have been exposed[Intrusion][Data leak]Leaked 8.4MOrganizations 1Disclosed 2025-04-24Updated 2026-10-23Kanagawa[Contained][Severity: Critical]
Konaka: DIFFERENCE order data leaked[Intrusion][Data leak][Service outage]Leaked 150.5KOrganizations 1Disclosed 2025-04-18Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Tokai University: ransomware disrupts systems[Ransomware][Service outage]Organizations 1Disclosed 2025-04-15Updated 2026-10-23Tokyo[Contained][Severity: Critical]
IIJ: data leakage from IIJ Secure MX Service[Web app exploit][Data leak]Leaked 4.1MOrganizations 1Disclosed 2025-04-08Updated 2026-10-23Tottori[Contained][Severity: Critical]
Nippon Ceramic: ransomware and data leakage[Ransomware][Data leak][Service outage]Leaked 37.6KOrganizations 1,500Disclosed 2025-03-19Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
Recruit: Hokkaido Jalan member data may have been exposed[Intrusion][Data leak][Service outage]Leaked 104KOrganizations 1Disclosed 2025-03-18Updated 2026-10-23Yamaguchi[Contained][Severity: Major]
Fast Retailing: staff and business-contact data may have been exposed[Intrusion][Misconfiguration][Data leak]Organizations 1Disclosed 2025-03-18Updated 2026-10-23Nagano[Resolved][Severity: Critical]
MinebeaMitsumi: file server intrusion[Intrusion][Credential abuse][Data leak]Leaked 160KOrganizations 1Disclosed 2025-03-13Updated 2026-10-23Yamaguchi[Contained][Severity: Critical]
University of East Asia: data server intrusion[Web app exploit][Data leak][Site defacement]Leaked 17.3KOrganizations 1Disclosed 2025-03-12Updated 2026-10-23Mie[Investigating][Severity: Critical]
Oyatsu Company: unauthorized access[Intrusion][Data leak][Service outage]Leaked 170KOrganizations 1Disclosed 2025-03-06Updated 2026-10-23Kanagawa[Contained][Severity: Critical]
Sunnet: inquiry attachments left publicly accessible[Misconfiguration][Data leak]Leaked 2.6KOrganizations 1,524Disclosed 2025-03-05Updated 2026-10-23Tokyo[Contained][Severity: Critical]
NTT Communications: corporate customer data may have been exposed[Intrusion][Data leak]Organizations 17,891Disclosed 2025-02-27Updated 2026-10-23Tokyo[Contained][Severity: Major]
Digital Technologies: intrusion and data leakage[Intrusion][Service outage][Data leak]Leaked 4.6KOrganizations 1Disclosed 2025-02-27Updated 2026-10-23Osaka[Contained][Severity: Major]
O-M: ransomware attack[Ransomware][Service outage][Data leak]Organizations 1Disclosed 2025-02-25Updated 2026-10-23Tokyo[Resolved][Severity: Critical]
Hoken Minaoshi Hompo Group: ransomware attack[Ransomware][Data leak][Service outage]Leaked 5.1MOrganizations 1Disclosed 2025-02-25Updated 2026-10-23Aomori[Contained][Severity: Critical]
Kashiwazaki Seika: card data exposed at its online shop[Web app exploit][Data leak]Leaked 1.3KOrganizations 1Disclosed 2025-02-21Updated 2026-10-23Tokyo[Resolved][Severity: Major]
Sony Music Solutions: Sony Music Shop cache settings showed other customers' data[Misconfiguration][Data leak]Leaked 658Organizations 1Disclosed 2025-02-18Updated 2026-10-23Tochigi[Contained][Severity: Critical]
Utsunomiya Central Clinic: ransomware attack[Ransomware][Service outage][Data leak]Leaked 300KOrganizations 1Disclosed 2025-02-07Updated 2026-10-23Osaka[Resolved][Severity: Major]
Oumiya: ransomware attack[Ransomware][Service outage][Data leak]Leaked 20KOrganizations 1Disclosed 2025-01-27Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Hands: Hands Club app breached; member data leaked[Intrusion][Data leak]Leaked 121.9KOrganizations 1Disclosed 2025-01-24Updated 2026-10-23Ibaraki[Contained][Severity: Major]
Junkosha: ransomware attack[Ransomware][Service outage][Data leak]Organizations 1Disclosed 2025-01-22Updated 2026-10-23Tokyo[Resolved][Severity: Critical]
Sanrio Entertainment: ransomware attack[Ransomware][Data leak][Service outage]Leaked 2MOrganizations 1Disclosed 2025-01-20Updated 2026-10-23Kanagawa[Resolved][Severity: Critical]
Kaikatsu Frontier: unauthorized access to Kaikatsu CLUB and FiT24 member data[Intrusion][Data leak][Service outage]Leaked 7.3MOrganizations 1Disclosed 2025-01-15Updated 2026-10-23Tokyo[Investigating][Severity: Major]
WECARS: customer data may have been disclosed through a former employee's phone synchronization[Unknown][Data leak]Leaked 152Organizations 1Disclosed 2025-01-05Updated 2026-10-23Tokyo[Resolved][Severity: Moderate]
Japan Weather Association: repeated DDoS attacks on tenki.jp[DDoS][Service outage]Organizations 1Disclosed 2025-01-02Updated 2026-10-23Tokyo[Contained][Severity: Minor]
NTT DOCOMO: DDoS attack disrupts goo and related services[DDoS][Service outage]Organizations 1Disclosed 2024-12-31Updated 2026-10-23Tokyo[Resolved][Severity: Moderate]
Mizuho Bank: suspected DDoS attack makes Mizuho Direct and other online banking hard to reach[DDoS][Service outage]Organizations 1Disclosed 2024-12-26Updated 2026-10-23Tokyo[Resolved][Severity: Moderate]
Japan Airlines: DDoS attack delays 71 flights[DDoS][Service outage]Organizations 1Disclosed 2024-12-26Updated 2026-10-23Tokyo[Resolved][Severity: Moderate]
MUFG Bank: DDoS attack makes Mitsubishi UFJ Direct and other online banking logins unstable[DDoS][Service outage]Organizations 1Disclosed 2024-12-13Updated 2026-10-23Fukuoka[Contained][Severity: Moderate]
Kyushu Tekko Center: ransomware encrypts files on several servers[Ransomware][Service outage]Organizations 1Disclosed 2024-12-11Updated 2026-10-23Osaka[Contained][Severity: Major]
Naniwa Pump Mfg.: ransomware through stolen credentials; employee data may have leaked[Ransomware][Credential abuse][Data leak][Service outage]Organizations 1Disclosed 2024-12-09Updated 2026-10-23Tokyo[Contained][Severity: Critical]
Sankei: personal data of 292,707 customers, including card data of 71,943, may have leaked from its old online shop[Web app exploit][Data leak][Fraud]Leaked 292.7KOrganizations 1Disclosed 2024-12-05Updated 2026-10-23Hokkaido[Investigating][Severity: Critical]
Iseki Hokkaido: ransomware; about 55,000 customer and employee records at risk[Ransomware][Data leak][Service outage]Leaked 53.6KOrganizations 1Disclosed 2024-12-03Updated 2026-10-23Fukushima, Miyagi[Contained][Severity: Moderate]
EXD: ransomware encrypts data on participants of Fukushima Prefecture and Koriyama City events[Ransomware][Service outage][Extortion]Leaked 5KOrganizations 4Disclosed 2024-12-02Updated 2026-10-23Kanagawa[Investigating][Severity: Moderate]
Kanagawa Arts Foundation: servers of the operator of the Kanagawa Prefectural Hall and other venues likely hit by ransomware[Ransomware][Service outage]Organizations 2Disclosed 2024-11-20Updated 2026-10-23Fukushima, Miyagi[Contained][Severity: Moderate]
Exceed Connect: Koriyama City KidZania event winners list emailed to the wrong address; 516 records at risk[Misdelivery][Data leak]Leaked 516Organizations 2