株式会社システムソフトData breach / unauthorized access incident
- Occurred on
- Unconfirmed
- Announced on
- April 8, 2026
- Severity
- BIncidents centered on names and contact details.
- Scale
- Unknown
- Main impact
- A ransomware incident occurred at subsidiary マムクリエイト, encrypting internal servers; data exfiltration has not been confirmed.
- Information involved
- Not specified in the disclosure
- Cause / key point
- Cause is under investigation.About Ransomware
- Industry
- IT & telecom
- Listing / capital
- Listed company東証スタンダード 7527(システムソフト)
- Last updated
- October 20, 2026
Stock price reaction to the disclosureシステムソフト / 東証スタンダード 7527
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Attack method classification: Ransomware(Encrypting data and demanding a ransom)
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