Isetan Mitsukoshi Co., Ltd and MI Card Co., Ltd announced, on 5 August 2020, that they had suffered a data breach affecting approximately 19,000 customers as a result of unauthorised access. In particular, MI Card noted that the data breach occurred on the Isetan Mitsukoshi Online Store as well as MI Card's homepage. In addition, MI Card highlighted that personal information such as name, address, phone number, email address, and date of birth of customers of the Mitsukoshi online store were accessed, whereas the member name, expected billing amount, and current membership points held on the MI Card homepage were also accessed. Moreover, MI Card outlined that it has strengthened its security
News
Japan: Mitsukoshi and MI Card announce data breach affecting approximately 19,000 customers
August 17, 2020
Summary
Isetan Mitsukoshi Co., Ltd and MI Card Co., Ltd reported a data breach on 5 August 2020, affecting about 19,000 customers due to unauthorized access. The breach exposed personal details of Isetan Mitsukoshi Online Store customers and MI Card homepage users, including names, addresses, contact information, and membership data. MI Card has since enhanced security measures, such as blocking suspicious IP addresses, upgrading security systems, and engaging with police and external experts.