mediaplex-2026 · Disclosed 2026-07-03
テレビ朝日メディアプレックス: unauthorized access and impact
Investigators report possible theft and abuse of authentication-federation account credentials. 1,343 employee, 2,786 applicant and 414 contact records leaked or may have leaked.
Outcome: Confirmed breach
Entry path and evidence
Timeline
Disclosure date established by the reviewed notice. [s1]
Reported response
- Reported fact
Affected servers and external connections were stopped; monitoring and controls were reviewed after forensics.
[s1]第2報 pp.1-3 §§1-5
Evidence relevant to prevention
Insufficient evidence
Undisclosed entry or patch timing prevents an avoidability assessment. Inspect privileges, retrieval logs, retention and deployed configuration using the linked rules.
Editorial assessment; not a determination of liability. [s1]
Unknowns and AI involvement
The reviewed disclosures do not establish attacker use of AI.
The authentication sequence is described as likely; the full entry chain and confirmed extraction scope are unresolved.
Sources
[s1] テレビ朝日メディアプレックス · Primary source
テレビ朝日メディアプレックス：事故に関する公表資料 ↗Reviewed 2026-10-09