SHINDO2

QUO Card

QUO CARD Co., Ltd.

Unauthorized accessSize not disclosed

POSSIBLE LEAKUsage history / Nickname / display nameInvestigating

Open in the live monitor ▶
Disclosed
Sep 29, 2026
Leak
Leak possible
Type
Unauthorized access
Status
Investigating
Security spend
Measures, no amount
Compensation
Not announced
Corporate number
2010001091242

What leaked

IdentityLINE display name
Transactions & activityCampaign prize-winning information

Not leaked

  • Special-care personal information and payment data such as credit card and bank account details were not held, so they did not leak
  • Special-care personal information and payment data such as credit card and bank account details were not held, so they did not leak
  • Special-care personal information and payment data such as credit card and bank account details were not held, so they did not leak

Who is affected

  • Participants in the LINE official account campaign

Cause

Unauthorized third-party access to the campaign system of the company's LINE official account. The system is dedicated to the campaign and separate from other systems, including payment systems

Timeline

  1. First disclosure

Response

  • Blocked the entry point
  • Notified individuals
  • Phishing warning

Identified the system that may have been accessed and took countermeasures. Customers who may be affected will be contacted individually once identified. Warned that the company never asks, by email, LINE or SMS, for passwords, card details, money transfers or authentication codes

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