Media and books

Mainichi Shimbun Digital

Mainichi Shimbun Digital (run by The Mainichi Newspapers Co., Ltd.) was hit in 1 recorded cybersecurity incident. The latest was disclosed on 2025-07-11.

About the service

Website

https://mainichi.jp/

Run by

The Mainichi Newspapers Co., Ltd.

Category

Media and books

For

People

Incident history

Disclosed 2025-07-11Updated 2025-09-11Tokyo[Resolved][Severity: Moderate][Breached][Moderate]
Mainichi Newspapers: credential stuffing on Mainichi Shimbun Digital logged into 21,752 IDs in three days, with no sign that personal data pages were viewed
[Credential abuse]Organizations 1

		Incident	Role	Impact level				Methods	Impacts		Status
2025-07-11	2025-09-11	Mainichi Newspapers: credential stuffing on Mainichi Shimbun Digital logged into 21,752 IDs in three days, with no sign that personal data pages were viewed	[Breached]	[Moderate]	[Moderate]	1 The Mainichi Newspapers Co., Ltd.	Tokyo	[Credential abuse]		Unknown	[Resolved]

Other incidents of the operator (1)

Disclosed 2026-10-19Updated 2026-10-28Aichi, Fukuoka, Kanagawa, Osaka, Saitama, Tokyo[Investigating][Severity: Critical]
Ymirlink: break-in at the Cuenote FC email delivery service exported about 51.6 million records from 49 customer systems
[Web app exploit][Data leak]Leaked 51.6MOrganizations 31

		Incident				Methods	Impacts		Status
2026-10-19	2026-10-28	Ymirlink: break-in at the Cuenote FC email delivery service exported about 51.6 million records from 49 customer systems	[Critical]	31 Central Japan Railway Company, Kyushu Railway Company, West Japan Railway Company, Bandai Namco Entertainment Inc., BANDAI SPIRITS Co., Ltd., Life Card Co., Ltd., Rise UP Co., Ltd., Ymirlink, Inc., Dai Nippon Printing Co., Ltd., DCM Co., Ltd., Nomura Securities Co., Ltd., Saitama Prefecture, istyle Inc., NTTPC Communications, Inc., Animate Ltd., The Asahi Shimbun Company, ASMARQ Co., Ltd., Cybozu, Inc., Impress Corporation, Japan Association for Financial Planners, JMA Management Center Inc., Kansai Mirai Bank, Limited, The Mainichi Newspapers Co., Ltd., Persona Co., Ltd., Resona Bank, Limited, Saitama Resona Bank, Limited, Satofull Co., Ltd., Sendenkaigi Co., Ltd., Sourcenext Corporation, Syuppin Co., Ltd., ValueCommerce Co., Ltd.	Aichi, Fukuoka, Kanagawa, Osaka, Saitama, Tokyo	[Web app exploit]	[Data leak]	51,628,280	[Investigating]