Security Knowledge
← Incident database

chibagin-shoten-2026 · Disclosed 2026-09-17

ちばぎん商店: unauthorized access and impact

A subsidiary website was altered; the entry route is under investigation. Potential exposure concerns approximately 722 individual and 1,616 corporate gift recipients; exfiltration evidence was not found.

Supply chain / CICause unresolved / undisclosed

Outcome: Confirmed breach

Entry path and evidence

  • Reported fact

    A subsidiary website was altered; the entry route is under investigation.

    [s1]p.1-2 §§1-3
  • Reported fact

    Potential exposure concerns approximately 722 individual and 1,616 corporate gift recipients; exfiltration evidence was not found.

    [s1]p.1-2 §§1-3

Timeline

  1. Disclosure date established by the reviewed notice. [s1]

Reported response

  • Reported fact

    The site was suspended and external links removed; specialists are investigating.

    [s1]p.1-2 §§1-3

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

AI involvementUnknown

The reviewed disclosures do not establish attacker use of AI.

The undisclosed details must remain unknown.

Sources

  1. [s1] ちばぎん商店 · Primary source

    ちばぎん商店：事故に関する公表資料 ↗

    Reviewed 2026-10-09