SHINDO3

Seino Transportation

Seino Transportation Co., Ltd.

Personal data~1,800records

POSSIBLE LEAKPassword / Postal addressUnauthorized access · Closed (final report)

Open in the live monitor ▶
Disclosed
Aug 2025
Detected
Aug 20, 2025
Detection to disclosure
-19 days
Leak
Leak possible
Type
Unauthorized access
Status
Closed (final report)
Security spend
Not checked yet
Compensation
Not announced

What leaked

IdentityFull name
ContactAddress, Phone number, Email address
CredentialsMember ID, Password

How many

  • Mitsukaru Soko registration records ~1,800 records
  • My Seino member IDs and passwords ~20 records

Who is affected

  • Service users

Cause

Unauthorized access to logistics-related services

Timeline

  1. Announced in August and services suspended
  2. Unauthorized access detected on Mitsukaru Soko
  3. Service restored
  4. Investigation results; no misuse confirmed

Response

  • Service stopped
  • Forensic investigation

Services suspended temporarily and investigated externally; resumed on September 12 after countermeasures

What you should do

  1. Change this password and every account that reused it now. Switch to a passkey where offered
  2. Don't open links in emails from this company. The apology email itself may be fake
  3. Treat refund or apology calls and texts as scams. Call back only on the number from the official site
  4. Watch for unexpected mail or invoices; your address is hard to change
  5. Check the company's notice to see if you're affected

Lessons for companies

  1. Report to the PPC: preliminary in 3–5 days, final in 30 (60 if malicious)
  2. Run red teaming and AI-assisted hardening, and publish how much you invest

Sources