> JapanHacked_Cybersecurity incidents in Japan

Company

Kumon Institute of Education Co., Ltd.

Kumon Institute of Education Co., Ltd. (Yodogawa, Osaka, Osaka; Education and learning support) appears in 1 related cybersecurity incident. The latest was disclosed on 2024-05-29.

Profile

Industry/type: Education and learning support
Location: Osaka, Osaka, Yodogawa
Website: https://www.kumon.ne.jp/

Public figures

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Metric	Value		As of	Source
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Incident history

Disclosed 2024-05-29Updated 2026-10-23Aichi, Ehime, Kyoto, Osaka, Tokushima, Tokyo, Wakayama[Contained][Severity: Critical][Through a supplier][Critical]
Iseto: ransomware leaks data of about 3.07 million people from about 100 client organizations
[Ransomware][Data leak]Leaked 3.1MOrganizations 13

		Incident	Role	Impact level				Methods	Impacts		Status
2024-05-29	2026-10-23	Iseto: ransomware leaks data of about 3.07 million people from about 100 client organizations	[Through a supplier]	[Critical]	[Critical]	13 Tokushima Prefectural Government, Toyota City, Wakayama City, Iseto Inc., The Iyo Bank, Ltd., Kumon Institute of Education Co., Ltd., Sumitomo Mitsui Trust Bank, Limited, Kubota Credit Co., Ltd., Kyoto Chamber of Commerce and Industry, Manulife Life Insurance Company, Nippon Life Insurance Company, Saikyo Shinkin Bank, Tokai Shinkin Business Inc.	Aichi, Ehime, Kyoto, Osaka, Tokushima, Tokyo, Wakayama	[Ransomware]	[Data leak]	3,076,477	[Contained]