A Japanese telecommunications company disclosed to customers last week that some of their data had been accessed by an unauthorised third party.
Sakura Mobile, which provides SIM cards, WiFi, and other services to international residents and visitors, said that it had detected the access last month.
“On 27 July 2026, our system was subject to unauthorised access from outside the company. We closed the route of entry and replaced credentials on the same day, and we are implementing measures to prevent recurrence,” Sakura Mobile’s representative director, Tomoki Sunaga, said in a 31 July email seen by Cyber Daily and sent to at least one Australian resident recently returned from the country.
“The relevant Japanese authorities have been notified regarding this incident, and we have reported all of the necessary details.”
According to the company, the breach impacts customers who placed a Travel Plan order on or after 4 November 2025 and on or before 27 July 2026, and who placed a Travel Plan order on or before 3 November 2025 with a service start date on or after 4 November 2025.
The Travel Plan is Sakura’s short-term travel option and covers SIM cards, eSIMs, and Pocket WiFi.
The data that “may” have been accessed includes names, email addresses, product order details, and payment methods. The company did not disclose how many of its customers have been impacted.
However, Sakura Mobile said credit card details were not impacted, as they are stored by the company’s payment processor. Similarly, neither passwords nor location data were compromised.
“Our payment provider was unaffected by this incident, and information retained by them remains secured,” Sakura said.
“Therefore, there is not a high risk that fraudulent card use or impersonation will occur as a result of this incident.”
Sakura Mobile said the relevant Japanese authorities had been informed. To date, no threat actor has claimed responsibility for the incident.
Who is Sakura Mobile?
Sakura Mobile provides telecommunications services to international students, tourists, and foreign residents.
The company offers English language customer service and has been used by more than half a million individuals since 2014.
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