SHINDO2

TOHO Co., Ltd.

Account takeoverSize not disclosed

LEAK UNCLEAREmail addressClosed (final report)

Open in the live monitor ▶
Disclosed
Apr 7, 2026
Leak
Unknown
Type
Account takeover
Status
Closed (final report)
Security spend
Not checked yet
Compensation
Not announced

What leaked

ContactPartner email addresses (spam recipients)

Who is affected

  • Some business partners

Cause

An employee's email account was misused to send many suspicious emails

Timeline

  1. Intrusion began
  2. Intrusion stopped
  3. First disclosure

Response

  • Blocked the entry point
  • Phishing warning

Applied security measures and disconnected the device; asked recipients to delete suspicious emails unopened

What you should do

  1. Don't open links in emails from this company. The apology email itself may be fake
  2. 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