Japanese information and communication technology (ICT) provider NTT Communications Corporation (NTT Com) has disclosed a data breach impacting nearly 18,000 corporate clients.
The incident, the telecoms firm says, occurred on February 5, when an unnamed threat actor accessed its internal systems, including those hosting information on services provided to customer companies.
NTT Com says it restricted access to a compromised system immediately after detecting suspicious communication behavior on February 5.
On February 15, however, it discovered unauthorized access to another compromised system and blocked access to it.
The threat actor, the company says, exfiltrated information on 17,891 customer companies, including contract numbers, customer names, contact names, phone numbers, email addresses, physical addresses, and information on service usage.
NTT Com says it will notify all impacted customers of the data breach.
“We will continue to further strengthen security measures and monitoring systems to prevent recurrence and further improve the quality of our services,” reads an automated translation of the company’s announcement.
The telecoms firm says only corporate customers were affected by the incident, as the compromised system did not store information on end users.
A subsidiary of telecommunications giant Nippon Telegraph and Telephone Corporation, NTT Com provides cloud, network, and security services for companies and government agencies in over 190 countries and regions.
Related: Indian Stock Broker Angel One Discloses Data Breach
Related: Finastra Starts Notifying People Impacted by Recent Data Breach
Related: 430,000 Impacted by Data Breaches at New York, Pennsylvania Healthcare Organizations
Related: Personal Information Compromised in GrubHub Data Breach