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MediumBreach · 2026-10-30

MUJI app breach: up to 27.26M customer records

What happened

Ryohin Keikaku, MUJI's operator, says its official app was breached. Access is blocked and a fix applied. No IOCs or entry vector published yet.

Who's affected

Up to 27.26M customers, including closed accounts. Data: emails, birth dates, gender. No names, addresses or cards.

✅ Fix / patch

  • Add MUJI-themed sale/points lures to mail filters and user awareness training.

🔎 Quick hunt check

No published indicators yet. Expect phishing that quotes real birthdays.

⏱ CISA deadline

Not in CISA KEV as of Oct 31, 2026.

Sources