Dentsu Digital breach shuts down Japan Post’s LINE service
SpilloverSpillover from the Dentsu Digital incident · View original incident →Japan Post’s official LINE service was suspended after TONARIWA, Dentsu Digital’s LINE account management platform, was compromised. The attacker used leaked administrator account credentials to gain unauthorized access and then escalated privileges. An investigation is examining whether Japan Post users’ personal information and LINE account-linking authentication information may have been leaked.
Key facts
- Affected organization
- Japan Post
- Original incident
- Dentsu Digital TONARIWA breach leaks personal data from two client companies
- Incident type
- Data breach
- Occurred / detected
- Not confirmed
- Scale of damage
- Suspension of the official LINE service and possible leak of user information
- Cause / method
- Unauthorized access and privilege escalation using stolen administrator account credentials for Dentsu Digital’s TONARIWA
- Location
- Japan
If your data was exposed
- Don’t tap links in texts, calls or emails that mention this incident and offer compensation, refunds or breach checks. Check directly on the organization’s official website or app.
Timeline
- It was revealed that Japan Post had suspended its official LINE service following the compromise of Dentsu Digital’s TONARIWA, and that a possible leak of personal information and LINE account-linking authentication information was under investigation.
Original incident
This is spillover from the Dentsu Digital incident.
Dentsu Digital TONARIWA breach leaks personal data from two client companies
Impact: Personal data from two client companies leaked; number of affected records under investigation
Unauthorized access and privilege escalation using leaked administrator account credentials were confirmed on Dentsu Digital's marketing platform TONARIWA. A follow-up announcement on November 12 confirmed logs showing that personal data from two client companies had been exfiltrated, with names, dates of birth, contact details, and LINE integration access tokens among the information identified as leaked. All servers were shut down and isolated, and the number of affected records is under investigation.
Related reports: 10 · last report →
5 related reports
- Potential Data Breach on Japan Post's LINE Official Account Following Unauthorized Access to Dentsu Digital Service
- 日本郵便「郵便局［ぽすくま］」LINEサービス停止 委託先 電通デジタルの「TONARIWA」に不正アクセス、情報漏えいのおそれ
- 日本郵便のLINE公式アカウントで情報漏えいのおそれ 電通デジタルのサービスに不正アクセス（アスキー）
- 日本郵便のLINE公式アカウントで情報漏えいのおそれ 電通デジタルのサービスに不正アクセス
- 電通デジタル「TONARIWA」に不正アクセス、管理アカウントの認証情報漏えいから権限昇格。LINE連携トークン流出のおそれで日本郵便のサービスも停止
The summary and key facts are written by AI from related reports and may contain errors. Check the original articles and the organization’s official statements for accurate details.