SHINDO2

Japan Arcadia Network

Unauthorized accessSize not disclosed

LEAK UNCLEARInvestigating

Open in the live monitor ▶
Disclosed
May 12, 2026
Detected
May 1, 2026 21:00 JST
Detection to disclosure
11 days
Leak
Unknown
Type
Unauthorized access
Status
Investigating
Security spend
Not checked yet
Compensation
Not announced

What leaked

UnspecifiedData on customer servers (no leak confirmed)

Who is affected

  • Client companies

Cause

Traces of third-party access and planted suspicious files were found in customer server environments it manages

Timeline

  1. Detected
  2. Contained
  3. First disclosure

Response

  • Notified individuals
  • Forensic investigation

Contacting customers individually; investigating scope and impact

What you should do

  1. 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