エスペック株式会社Data breach / unauthorized access incident
- Occurred on
- Unconfirmed
- Announced on
- April 21, 2026
- Severity
- SCompromise of deep personal data or usable credentials.
- Scale
- 1 accounts
- Main impact
- An employee's email account was accessed without authorization, suspicious emails were sent, and contacts' email addresses and signature information may have been viewed.
- Information involved
- Email addressAuth tokenFull name
- Cause / key point
- The company says credentials were likely stolen via a brute-force attack, resulting in the unauthorized access.About Abuse of credentials
- Industry
- Manufacturing
- Listing / capital
- Listed company東証プライム 6859(エスペック)
- Last updated
- October 20, 2026
Stock price reaction to the disclosureエスペック / 東証プライム 6859
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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: Abuse of credentials(Logging in legitimately with leaked or guessed passwords)
Read the Abuse of credentials guide and national trends →