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Government

Sumida safety mail

Sumida safety mail (run by Sumida City) was hit in 1 recorded cybersecurity incident. The latest was disclosed on 2026-10-13.

About the service

Website

https://www.city.sumida.lg.jp/anzen_anshin/kurasinoanzen_ansin/anzen_ansin_mail1.html

Run by

Sumida City

Category

Government

For

People

Incident history

Disclosed 2026-10-13Updated 2026-11-04Aichi, Aomori, Chiba, Fukuoka, Hiroshima, Hyogo, Kagawa, Kagoshima, Kanagawa, Oita, Okayama, Okinawa, Osaka, Saitama, Tochigi, Tokyo[Investigating][Severity: Critical][Precautionary halt][Moderate]
Arcadia: SpeeCAN RAIDEN intrusion disrupts safety alerts and puts registration data at risk
[Web app exploit][Data leak][Service outage]Leaked 3.1MOrganizations 36

		Incident	Role	Impact level				Methods	Impacts		Status
2026-10-13	2026-11-04	Arcadia: SpeeCAN RAIDEN intrusion disrupts safety alerts and puts registration data at risk	[Precautionary halt]	[Moderate]	[Critical]	36 Arcadia, Inc., Takehara City, Aichi Prefectural Police, Chiba Prefectural Government, City of Yokohama, 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, Aomori City, Chiba City, Fukuyama City, Hadano City, Hatsukaichi City, Kagawa Prefectural Police, Kagawa Prefecture, Oita City, Okazaki City, Yokosuka City, Zama City, Ayase City, Ichikai Town, Kanuma City, Minamiboso City, Nasukarasuyama City, Shioya Town, Tarama Village, Sumida City	Aichi, Aomori, Chiba, Fukuoka, Hiroshima, Hyogo, Kagawa, Kagoshima, Kanagawa, Oita, Okayama, Okinawa, Osaka, Saitama, Tochigi, Tokyo	[Web app exploit]	[Data leak][Service outage]	3,136,000	[Investigating]

Other incidents of the operator (1)

Disclosed 2021-03-02Updated 2021-06-04Chiba, Hokkaido, Osaka, Tokyo[Resolved][Severity: Major]
Landbrain: ransomware on its servers
[Ransomware][Extortion]Organizations 11

		Incident				Methods	Impacts		Status
2021-03-02	2021-06-04	Landbrain: ransomware on its servers	[Major]	11 Landbrain Inc., Cabinet Secretariat, Ministry of Internal Affairs and Communications, Tokyo Metropolitan Government, Ibaraki City, Kishiwada City, Adachi City, Arakawa City, Asahikawa City, Shibayama Town, Sumida City	Chiba, Hokkaido, Osaka, Tokyo	[Ransomware]	[Extortion]	Unknown	[Resolved]