> JapanHacked_Cybersecurity incidents in Japan

Company

Nagano Toshi Gas Inc.

Nagano Toshi Gas Inc. (Nagano, Nagano; Electricity, gas, heat and water) appears in 1 related cybersecurity incident. The latest was disclosed on 2026-08-15.

Profile

Industry/type: Electricity, gas, heat and water
Location: Nagano, Nagano
Website: https://www.nagano-toshi-gas.co.jp/

Public figures

Employees2312024-04-03
METI: Gビズインフォ

Metric	Value		As of	Source
Employees	231		2024-04-03	METI: Gビズインフォ

Incident history

Disclosed 2026-08-15Updated 2026-10-23Gunma, Mie, Nagano, Saitama[Investigating][Severity: Critical][Through a supplier][Major]
Ryomo Systems: ransomware attack
[Ransomware][Credential abuse][Data leak]Organizations 5

		Incident	Role	Impact level				Methods	Impacts		Status
2026-08-15	2026-10-23	Ryomo Systems: ransomware attack	[Through a supplier]	[Major]	[Critical]	5 Isesaki City, Ryomo Systems Co., Ltd., Daito Gas Inc., Nabari Kintetsu Gas Inc., Nagano Toshi Gas Inc.	Gunma, Mie, Nagano, Saitama	[Ransomware][Credential abuse]	[Data leak]	Unknown	[Investigating]