CPossible leakOctober 2, 2026 announced

独立行政法人石油天然ガス・金属鉱物資源機構（JOGMEC）Data breach / unauthorized access incident

Reviewed by Yutaro SasaoWritten by Leak Watch editorial teamOctober 2, 2026 published ・ October 20, 2026 updated

Occurred on: September 9, 2026
Announced on: October 2, 2026
Severity: CLimited data such as email addresses and identifiers.
Scale: 8,500 records
Main impact: Due to unauthorized external access, approximately 1,100 staff email addresses and about 7,400 non-organization email addresses, a total of about 8,500 email addresses, may have been leaked.
Information involved: Email address
Cause / key point: It is believed to have been caused by unauthorized external access that penetrated the information system.
Industry: Government & municipal
Listing / capital: Government / public body
Independent Administrative Institution (national agency)
Sources: JOGMEC（2026-10-02）
Last updated: October 20, 2026

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Written & reviewed

Reviewed byYutaro SasaoFounder & CEO, MediaLeap Inc.

CEO of MediaLeap Inc. Working on both sides of web advertising and web media since 2013; founded the company in May 2025.

Review scope: cross-checking against primary sources (official and government announcements), verifying claims stay within the facts, and checking source attribution。Last reviewed: October 20, 2026

Written by:Leak Watch editorial team (AI-assisted drafts verified against sources by the editorial team) · Reviewer profile · Request a correction

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Attack method classification: Unauthorized access (method undisclosed)(Breached, but the technique was not identified or disclosed)

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