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 2026-10-21Updated 2026-10-21Tokyo[Contained][Severity: Critical]
OTOTOY: unauthorized access to the OTOTOY music store[Intrusion][Data leak][Service outage]Leaked 480KOrganizations 1Disclosed 2026-10-21Updated 2026-10-21Tokyo[Investigating][Severity: Major]
PingCAP: unauthorized access to internal systems[Credential abuse][Data leak]Leaked 50KOrganizations 1Disclosed 2026-10-21Updated 2026-10-21Tokyo[Investigating][Severity: Moderate]
Shinryo: cyberattack causes a system outage[Intrusion][Service outage]Organizations 1Disclosed 2026-10-21Updated 2026-10-21Tokyo[Contained][Severity: Critical]
Valuence Japan: online purchase system intrusion[Intrusion][Data leak]Leaked 1.2KOrganizations 1Disclosed 2026-10-20Updated 2026-10-26Fukuoka, Tokyo[Investigating][Severity: Major]
GoWeb Cloud: GoWeb SQL injection[Web app exploit][Data leak]Organizations 3Disclosed 2026-10-20Updated 2026-10-23Tokyo[Investigating][Severity: Major]
Fuji TV: programme system intrusion[Intrusion][Data leak]Leaked 543Organizations 1Disclosed 2026-10-20Updated 2026-10-21Tokyo[Ongoing][Severity: Minor]
Monex: attempted access prompts precautionary account-opening pause[Unknown][Service outage]Organizations 1Disclosed 2026-10-20Updated 2026-10-20 12:30Tokyo[Investigating][Severity: Moderate]
Youji Katsudo Kenkyukai: company network intrusion[Intrusion]Organizations 1Disclosed 2026-10-20Updated 2026-10-20Tokyo[Investigating][Severity: Critical]
Trustbank: unauthorized access to Furusato Choice[Intrusion][Data leak][Service outage]Leaked 4.5MOrganizations 1Disclosed 2026-10-20Updated 2026-10-20Tokyo[Investigating][Severity: Critical]
Globee: abceed intrusion[Misconfiguration][Data leak]Leaked 10.8KOrganizations 1Disclosed 2026-10-20Updated 2026-10-20Tokyo[Investigating][Severity: Critical]
Hakuhodo: Housing Energy Saving 2024 system misuse[Intrusion][Data leak][Service outage]Leaked 23.9KOrganizations 2Disclosed 2026-10-20Updated 2026-10-20Tokyo[Contained][Severity: Critical]
Aidma Holdings: Mamaworks intrusion[Misconfiguration][Data leak]Organizations 1Disclosed 2026-10-19Updated 2026-10-30 13:39Tokyo[Investigating][Severity: Critical]
Papyless Renta!: partial reading service resumes after intrusion shutdown[Unknown][Service outage][Data leak]Organizations 1Disclosed 2026-10-19Updated 2026-10-30Aichi, Fukuoka, Kanagawa, Osaka, Saitama, Tokyo[Investigating][Severity: Critical]
Ymirlink: Cuenote FC mail system intrusion[Web app exploit][Data leak]Leaked 51.6MOrganizations 32Disclosed 2026-10-19Updated 2026-10-22Tokyo[Investigating][Severity: Moderate]
SoftBank: My SoftBank unauthorized access attempt[Unknown][Service outage]Organizations 1Disclosed 2026-10-19Updated 2026-10-20Tokyo[Ongoing][Severity: Moderate]
Square Enix: unauthorized logins to Square Enix accounts[Credential abuse]Organizations 1Disclosed 2026-10-19Updated 2026-10-20Tokyo[Contained][Severity: Major]
Japan Post Holdings: credential stuffing against Yu ID[Credential abuse][Data leak][Service outage]Leaked 249Organizations 1Disclosed 2026-10-19Updated 2026-10-19 20:30Tokyo[Contained][Severity: Major]
ZIGZAG: WorldShopping intrusion[Web app exploit][Data leak]Leaked 301Organizations 1Disclosed 2026-10-19Updated 2026-10-19 17:53Tokyo[Investigating][Severity: Major]
Entouch: ransomware attackers access remote meeting database[Intrusion][Data leak]Organizations 2Disclosed 2026-10-19Updated 2026-10-19Shizuoka, Tokyo[Investigating][Severity: Major]
hokan: hokan Suito registration abuse and data theft[Web app exploit][Data leak]Leaked 13.3KOrganizations 2Disclosed 2026-10-19Updated 2026-10-19Tokyo[Investigating][Severity: Major]
JETRO: unauthorized access to its websites[Intrusion][Data leak][Service outage]Leaked 743Organizations 1Disclosed 2026-10-19Updated 2026-10-19Tokyo[Investigating][Severity: Major]
LIXIL: L-Pocket intrusion[Intrusion][Data leak][Service outage]Leaked 3.4KOrganizations 1Disclosed 2026-10-19Updated 2026-10-19Tokyo[Investigating][Severity: Critical]
NIFTY: line application management system intrusion[Intrusion][Data leak]Leaked 542.5KOrganizations 1Disclosed 2026-10-19Updated 2026-10-19Tokyo[Contained][Severity: Major]
Rakumachi: Rakumachi credential stuffing[Credential abuse][Data leak]Leaked 3.5KOrganizations 1Disclosed 2026-10-18Updated 2026-10-21Tokyo[Contained][Severity: Moderate]
Japan Football Association: JFA Passport app attack[Intrusion][Service outage]Organizations 1Disclosed 2026-10-16Updated 2026-10-30Aichi, Aomori, Chiba, Fukuoka, Fukushima, Gifu, Hiroshima, Hokkaido, Kagawa, Kagoshima, Kanagawa, Kochi, Kyoto, Mie, Miyagi, Nagano, Nagasaki, Niigata, Okayama, Okinawa, Saitama, Shiga, Tokyo, Toyama, Wakayama, Yamanashi[Investigating][Severity: Critical]
Studio: website builder cloud environment intrusion[Web app exploit][Data leak]Organizations 72Disclosed 2026-10-16Updated 2026-10-29 08:05Tokyo[Resolved][Severity: Moderate]
Sumitomo Mitsui DS Asset Management: direct-sales site contractor intrusion[Intrusion][Service outage]Organizations 1Disclosed 2026-10-16Updated 2026-10-29Aichi, Ishikawa, Osaka, Tokyo[Investigating][Severity: Major]
WASABI: WASABI SWITCH leaks customer data; BuySell group reports 1,369 order records[Intrusion][Data leak]Leaked 1.4KOrganizations 5Disclosed 2026-10-16Updated 2026-10-23Osaka, Tokyo[Contained][Severity: Critical]
Trade Works: intrusion leaks IwaiCosmo data and places orders[Intrusion][Misconfiguration][Data leak][Fraud][Financial loss]Leaked 5KOrganizations 2Disclosed 2026-10-16Updated 2026-10-16Tokyo[Investigating][Severity: Major]
Astemo: unauthorized access to its data sharing cloud[Credential abuse][Data leak][Extortion]Leaked 350Organizations 1Disclosed 2026-10-16Updated 2026-10-16Tokyo[Contained][Severity: Major]
Japan Arts: Google account phishing[Phishing][Data leak]Leaked 5.4KOrganizations 1Disclosed 2026-10-16Updated 2026-10-16Tokyo[Resolved][Severity: Moderate]
Mitsubishi Gas Chemical: T4C staff data email misdelivery[Misdelivery][Data leak]Leaked 2.1KOrganizations 2Disclosed 2026-10-16Updated 2026-10-16Tokyo[Investigating][Severity: Critical]
Nikkei: intrusion into its system development cloud service[Credential abuse][Data leak]Leaked 1.8MOrganizations 1Disclosed 2026-10-16Updated 2026-10-16Tokyo[Investigating][Severity: Major]
Nikken Gakuin: intrusion into its condominium manager course system[Intrusion][Data leak]Leaked 3.6KOrganizations 2Disclosed 2026-10-16Updated 2026-10-16Tokyo[Investigating][Severity: Major]
STANDS: Onboarding admin system intrusion[Credential abuse][Data leak][Service outage]Organizations 1Disclosed 2026-10-15Updated 2026-10-23Tokyo[Investigating][Severity: Critical]
Medley: unauthorized access to the @link clinic system[Intrusion][Malware][Service outage][Data leak]Organizations 1Disclosed 2026-10-15Updated 2026-10-20Tokyo[Contained][Severity: Critical]
Beauty Garage: unauthorized access to its online store[Intrusion][Data leak]Leaked 775.7KOrganizations 1Disclosed 2026-10-15Updated 2026-10-16Tokyo[Investigating][Severity: Major]
M3: MR-kun intrusion[Intrusion][Data leak]Organizations 1Disclosed 2026-10-15Updated 2026-10-16Tokyo[Contained][Severity: Critical]
Sourcenext: member data leak[API abuse][Data leak]Leaked 22.5MOrganizations 1Disclosed 2026-10-15Updated 2026-10-15Tokyo[Contained][Severity: Critical]
Burger King: app member data leak[Intrusion][Data leak]Leaked 11.2MOrganizations 1Disclosed 2026-10-15Updated 2026-10-15Osaka, Tokyo[Investigating][Severity: Critical]
Daiwa Institute of Research: Naito Securities' online trading system intrusion[Intrusion][Data leak]Leaked 631Organizations 2Disclosed 2026-10-14Updated 2026-10-22Tokyo[Investigating][Severity: Critical]
Carry: Lili matching site server intrusion[Web app exploit][Data leak]Leaked 98.3KOrganizations 1Disclosed 2026-10-14Updated 2026-10-20Tokyo[Resolved][Severity: Critical]
Aena: unauthorized access to its shopping app[Intrusion][Data leak]Leaked 817.2KOrganizations 1Disclosed 2026-10-14Updated 2026-10-14Tokyo[Contained][Severity: Critical]
NTV Wands: FaveConnect unauthorized logins[Credential abuse][Data leak]Leaked 117.4KOrganizations 1Disclosed 2026-10-13Updated 2026-10-30Tokyo[Investigating][Severity: Major]
East Japan Mitsubishi Motor Sales: Microsoft 365 unauthorized logins[Credential abuse][Data leak]Leaked 24.5KOrganizations 1Disclosed 2026-10-13Updated 2026-10-21Tokyo[Contained][Severity: Critical]
Fivot: IDARE intrusion[Web app exploit][Data leak]Leaked 129.7KOrganizations 1Disclosed 2026-10-13Updated 2026-10-16Tokyo[Investigating][Severity: Major]
Golf Digest Online: unauthorized access to its servers[Intrusion][Data leak][Service outage]Leaked 1.8KOrganizations 1Disclosed 2026-10-13Updated 2026-10-13Tokyo[Investigating][Severity: Critical]
Ride On Express: ransomware at Gin no Sara server supplier[Ransomware][Service outage][Data leak]Leaked 6.5MOrganizations 1Disclosed 2026-10-09Updated 2026-10-28Tokyo[Investigating][Severity: Critical]
Adventure: unauthorized access to skyticket servers[Intrusion][Data leak]Leaked 14.6MOrganizations 1Disclosed 2026-10-09Updated 2026-10-09Tokyo[Contained][Severity: Major]
coconala: Coconala Skill Market intrusion[Web app exploit][Data leak]Leaked 1.8KOrganizations 1