SHINDO3
Shingu Gas
Shingu Gas Co., Ltd.
Customer records~1,460records
POSSIBLE LEAKPostal address / Phone numberRansomware · Investigating
Open in the live monitor ▶- Disclosed
- Sep 30, 2026
- Leak
- Leak possible
- Type
- Ransomware
- Status
- Investigating
- Security spend
- Measures, no amount
- Compensation
- Not announced
- Corporate number
- 5170001011479
What leaked
IdentityFull name
ContactAddress, Phone number
Account dataBilling number
Not leaked
- Bank account numbers and credit card information are not included
- Bank account numbers and credit card information are not included
How many
- Customer records ~1,460 records
Who is affected
- Customers
Cause
The file server of Ryomo Systems, to which the company outsources customer information management, suffered unauthorized access by ransomware
Timeline
- First disclosure
Response
- Notified individuals
- Phishing warning
- Hotline
Affected customers are being contacted individually. Warning about suspicious contacts pretending to be the company. Contacts: Shingu Gas customer desk (0735-21-6431, weekdays and Saturdays 8:30-17:00) and Ryomo Systems (0120-998-970)
What you should do
- Treat refund or apology calls and texts as scams. Call back only on the number from the official site
- Watch for unexpected mail or invoices; your address is hard to change
- Check the company's notice to see if you're affected
Lessons for companies
- Put security requirements, audit rights and reporting deadlines in vendor contracts
- Offline backups with restore drills; segment the network
- Report to the PPC: preliminary in 3–5 days, final in 30 (60 if malicious)
- Run red teaming and AI-assisted hardening, and publish how much you invest
Sources
- Shingu Gas Co., Ltd. Official notice · Sep 30, 2026
- National Tax Agency Corporate Number Publication Site Registry
- Nikkei (headline only) News