NTT / docomo suffers significant data breach

Japanese telecom giant NTT Communications Corporation has experienced a significant data breach, compromising sensitive information of nearly 18,000 corporate customers. 

The breach was first detected on February 5, 2025, when unauthorized access to NTT's Order Information Distribution System was discovered.

This system contained critical customer data, including:

• - Customer names
• - Contract numbers
• - Phone numbers
• - Email addresses
• - Physical addresses
• - Service usage details

NTT promptly blocked access to the compromised system by February 6. However, further investigation revealed that attackers had pivoted to another network device by February 15, which was also swiftly disconnected. The company has since confirmed that the threat has been fully contained.

The breach exclusively affected corporate customers, with no personal consumer data reported as compromised. NTT opted for a public announcement rather than individual notifications to impacted customers as would be usual in such cases, mphasizing transparency in its response. 

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