Sakura Internet Data Breach May Affect More Than 1.36 Million Accounts

Sakura Internet, a Japanese cloud computing and data center provider, has disclosed a security breach involving unauthorized access to its sales management system, which stores customer contract and membership information.

In an updated security notice issued in response to its initial notification on Monday, the company said the incident may have affected up to 1,360,563 member accounts.

However, the exact number of affected accounts remains unknown while Sakura Internet continues investigating the breach.

Sakura Internet is a major Japanese digital infrastructure provider offering web hosting, virtual private servers, public cloud services, data centers, and GPU computing.

The company was selected as a domestic provider for Japan’s Government Cloud Program, making it a strategically important technology company as the country works to reduce its dependence on foreign hyperscalers.

According to Sakura Internet, attackers first gained access to its IT systems on August 9. The intrusion was discovered during an investigation into a separate breach involving the company’s Sakura Rental Server Service.

The earlier incident involved unauthorized logins to 583 accounts, access to customer-facing systems and customer data, and the installation of malware on Sakura’s systems.

Sakura Internet said it has disabled all compromised credentials and removed the malware. However, the discovery of unauthorized access to its sales management system has significantly expanded the scope of the investigation.

Based on the information collected so far, up to 1,360,563 accounts may have been exposed. The company has not confirmed that data was stolen or misused.

Sakura said passwords stored in the affected systems are hashed and would be difficult to decipher even if obtained by attackers. The company also confirmed that credit card information was not stored on the compromised systems.

The company has reported the Sakura Internet data breach to the relevant authorities and is contacting customers whose accounts may have been affected.

Sakura has not disclosed what type of malware was identified in its environment. The company also did not report any operational disruptions or outages related to the incident.

BleepingComputer has not found any ransomware or data extortion group claiming responsibility for the attack. We contacted Sakura Internet for additional information but had not received a response at the time of publication.

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