Mainichi.Jp Muji Data Breach Exposes 1.09 Million Customer Records
Article Content
- •1.09 million customer records may have been compromised in Muji's data breach.
- •345,000 valid credit card numbers and dates of birth are included in the leaked data.
- •Muji has temporarily halted its online services to enhance cybersecurity.
Ryohin Keikaku, operator of Muji, reported a data breach on November 4, 2026, potentially exposing 1.09 million customer records, including 345,000 valid credit card numbers and dates of birth. The breach was attributed to unauthorized access to its systems, which also affected other companies like Nomura Investor Relations and Bic Camera. Following this incident, Muji temporarily shut down its online store and app to enhance cybersecurity measures. The company had previously indicated that up to 27.26 million customer records could have been compromised due to unauthorized access to its Muji App. Nomura Investor Relations also confirmed unauthorized access to its Institutional Navi service, although the extent of the data leak remains under investigation. Other firms, including Bic Camera and regional airlines, reported similar breaches linked to an email distribution system managed by Arara. The situation is ongoing, with investigations still in progress.
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