> JapanHacked_Cybersecurity incidents in Japan

Government

Nasukarasuyama City

Nasukarasuyama City (Nasukarasuyama, Tochigi; Municipality) appears in 1 related cybersecurity incident. The latest was disclosed on 2026-10-13.

Profile

Industry/type: Municipality
Location: Tochigi, Nasukarasuyama
Website: https://www.city.nasukarasuyama.lg.jp/

Public figures

Residents22,9352026-01-01
MIC: 住民基本台帳に基づく人口、人口動態及び世帯数（令和8年1月1日現在）

Metric	Value		As of	Source
Residents	22,935		2026-01-01	MIC: 住民基本台帳に基づく人口、人口動態及び世帯数（令和8年1月1日現在）

Incident history

Disclosed 2026-10-13Updated 2026-10-26 12:51Aichi, Chiba, Fukuoka, Hiroshima, Hyogo, Kagoshima, Kanagawa, Oita, Okayama, Osaka, Saitama, Tochigi[Investigating][Severity: Critical][Through a supplier][Major]
Arcadia: unauthorized access to the SpeeCAN RAIDEN alert service
[Web app exploit][Data leak][Service outage]Leaked 3.1MOrganizations 28

		Incident	Role	Impact level				Methods	Impacts		Status
2026-10-13	2026-10-26 12:51	Arcadia: unauthorized access to the SpeeCAN RAIDEN alert service	[Through a supplier]	[Major]	[Critical]	28 Arcadia, Inc., Takehara City, Aichi Prefectural Police, Chiba Prefectural Government, Fukuoka Prefectural Police, Hiroshima City, Hiroshima Prefectural Police, Hyogo Prefectural Police, Kagoshima Prefectural Police, Kanagawa Prefectural Police, Nagoya City, Oita Prefectural Government, Okayama Prefectural Police, Saitama City, Saitama Prefectural Police, Tochigi Prefectural Police, Chiba City, Fukuyama City, Hadano City, Hatsukaichi City, Oita City, Okazaki City, Yokosuka City, Ichikai Town, Kanuma City, Minamiboso City, Nasukarasuyama City, Shioya Town	Aichi, Chiba, Fukuoka, Hiroshima, Hyogo, Kagoshima, Kanagawa, Oita, Okayama, Osaka, Saitama, Tochigi	[Web app exploit]	[Data leak][Service outage]	3,136,000	[Investigating]