エン（ミドルの転職）Data breach / unauthorized access incident
- Occurred on
- May 26, 2026
- Announced on
- June 5, 2026
- Severity
- SCompromise of deep personal data or usable credentials.
- Scale
- 2,503 records
- Main impact
- A total of 2,503 unauthorized logins due to list-based attacks were confirmed, and it is possible that member information pages were accessed. There is a risk that member information was viewed.
- Information involved
- Not specified in the disclosure
- Cause / key point
- Unauthorized logins due to list-based attacks were confirmed.About Abuse of credentials
- Industry
- Services & other
- Listing / capital
- Listed company東証プライム 4849(エン)
- Last updated
- October 20, 2026
Stock price reaction to the disclosureエン / 東証プライム 4849
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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:
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 →