マルタケData breach / unauthorized access incident
- Occurred on
- April 27, 2026
- Announced on
- June 24, 2026
- Severity
- AFinancial and HR records — information that easily translates into monetary damage.
- Scale
- Unknown
- Main impact
- Ransomware disrupted normal operations, and pharmaceutical supply was maintained by alternative means. It was confirmed that information on business partners, shareholders, and officers/employees was exfiltrated and publicly disclosed.
- Information involved
- Not specified in the disclosure
- Cause / key point
- Unauthorized access to servers using fraudulently created account credentials.About Ransomware
- Industry
- Healthcare
- Listing / capital
- Unlisted
- Last updated
- October 20, 2026
Is this incident worth paying attention to?
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:
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: Ransomware(Encrypting data and demanding a ransom)
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