スマレジ（スマレジEC）Data breach / unauthorized access incident
- Occurred on
- Unconfirmed
- Announced on
- September 25, 2026
- Severity
- AFinancial and HR records — information that easily translates into monetary damage.
- Scale
- Unknown
- Main impact
- Unauthorized access occurred to four company environments of スマレジEC, and customer and order information as well as administrator information may have been viewed or obtained; the number of affected individuals has not been disclosed.
- Information involved
- Email addressUser / member IDPasswordAuth tokenPhone numberHome addressFull name
- Cause / key point
- スマレジ states that a vulnerability in the login function of the customer management screen was exploited.About Exploitation of vulnerabilities
- Industry
- Retail & e-commerce
- Listing / capital
- Listed company東証グロース 4431(スマレジ)
- Last updated
- October 20, 2026
Stock price reaction to the disclosureスマレジ / 東証グロース 4431
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CEO of MediaLeap Inc. Working on both sides of web advertising and web media since 2013; founded the company in May 2025.
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Attack method classification: Exploitation of vulnerabilities(Breaking in through holes in software and devices)
Read the Exploitation of vulnerabilities guide and national trends →