Sakura Internet Hack May Have Exposed Data of Up to 1.36 Million Accounts

Japanese cloud and data center provider Sakura Internet has disclosed a security incident affecting its sales management system, where customer contract and membership information is stored. According to a report from BleepingComputer, the company updated its initial notification on Monday, stating that up to 1,360,563 member accounts may have been impacted, though the exact number remains under investigation.

Sakura Internet is a major domestic digital infrastructure provider in Japan, offering web hosting, VPS, public cloud, data-center, and GPU computing services. It has been selected as a provider for Japan’s Government Cloud program, giving it strategic importance in reducing dependence on foreign hyperscalers, BleepingComputer noted.

The company said hackers accessed its IT system on August 9. The intrusion was discovered later during an investigation into a separate breach at the Sakura Rental Server service. That earlier incident involved unauthorized logins to 583 accounts, access to customer-facing systems and client data, and installation of malware on Sakura systems. The company has invalidated the abused credentials and removed the malware. However, the discovery of the larger exposure makes the overall incident more significant, according to BleepingComputer.

Based on data gathered so far, 1,360,563 accounts were potentially compromised, but no data exfiltration has been confirmed. The company stated that stored passwords are hashed and would be difficult to decipher if stolen. It also specified that the compromised system does not store credit card information. Sakura has informed relevant authorities and is notifying affected customers individually about the exposure.

BleepingComputer reported that it is unclear what type of malware was detected in Sakura’s environment, but the company did not mention any operational or service disruptions. The publication also said it could not find a ransomware or data extortion threat actor claiming the attack. BleepingComputer contacted Sakura Internet for additional information but had not received a response at the time of writing.

The incident highlights the risks facing critical infrastructure providers, especially those involved in government cloud services. While the company has not confirmed any data theft, the potential exposure of over a million accounts underscores the need for robust security measures. BleepingComputer’s reporting will be updated as more information becomes available.