Skip to content
JAENES
APossible leakMay 12, 2026 announced

株式会社オリエンタルダイヤモンドData breach / unauthorized access incident

笹尾 祐太朗の写真Reviewed by Yutaro SasaoWritten by Leak Watch editorial team published ・ updated
Occurred on
May 4, 2026
Announced on
May 12, 2026
Severity
AFinancial and HR records — information that easily translates into monetary damage.
Scale
Unknown
Main impact
The company announced that a ransomware attack encrypted files and halted operations; external connections have been restricted while recovery is underway. Whether data was exfiltrated and the extent of any leak are undetermined.
Information involved
Phone numberHome addressFull name
Cause / key point
The cause is under investigation.About Ransomware
Industry
Manufacturing
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Phone numberHome addressFull nameHow severity is assessed →

Is this incident worth paying attention to?

Written & reviewed

笹尾 祐太朗の写真

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:

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

Related incidents

Browse the database →

Incidents sharing the same company, service, attack method or industry (grouped automatically from the disclosures).

Same attack method

Same industry

Attack method classification: Ransomware(Encrypting data and demanding a ransom)

Read the Ransomware guide and national trends →

← Back to Breach Watch