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Company

Yamagata Kotsu Co., Ltd.

Yamagata Kotsu Co., Ltd. (Yamagata, Yamagata; Transport and postal services) appears in 1 related cybersecurity incident. The latest was disclosed on 2026-04-03.

Profile

Industry/type: Transport and postal services
Location: Yamagata, Yamagata
Website: https://www.yamagatakotsu.jp/

Public figures

Employees5192026-04-10
METI: Gビズインフォ

Metric	Value		As of	Source
Employees	519		2026-04-10	METI: Gビズインフォ

Incident history

Disclosed 2026-04-03Updated 2026-10-23Yamagata[Contained][Severity: Critical][Through a supplier][Critical]
YCC Information System: ransomware attack
[Ransomware][Credential abuse][Data leak][Service outage]Leaked 121.9KOrganizations 7

		Incident	Role	Impact level				Methods	Impacts		Status
2026-04-03	2026-10-23	YCC Information System: ransomware attack	[Through a supplier]	[Critical]	[Critical]	7 Yamagata City, Yamagata Kotsu Co., Ltd., YCC Information System Inc., Yamagata Prefectural Government, Shonai Town, Takahata Town, Yamagata University	Yamagata	[Ransomware][Credential abuse]	[Data leak][Service outage]	121,880	[Contained]