[2025 Audit] KT, Hit by Hacking Incident, Holds USIM Inventory for Only 3% of Subscribers... 900,000 in Stock

"KT's Response Deemed Excessively Passive... Concerns Over Subscriber Inconvenience"

It has been revealed that KT currently holds only about 900,000 replacement USIM cards, which amounts to just 3% of its total subscribers. KT recently experienced a data breach in which the personal information of some subscribers, including USIM information, was leaked.

According to the office of Kim Hyun, a member of the National Assembly’s Science, ICT, Broadcasting and Communications Committee, as of October 14, KT’s USIM inventory stands at approximately 900,000 units, accounting for only 3.3% of its 27 million subscribers.

Kim Hyun, Democratic Party of Korea. Yonhap News Agency

Recently, 362 KT users suffered unauthorized small payment damages totaling about 240 million won. The mobile phone numbers, international mobile subscriber identity (IMSI), and international mobile equipment identity (IMEI) of 20,030 customers who had a history of receiving signals from illegal micro base stations (femtocells) were also leaked.

Assemblywoman Kim pointed out, "There are still concerns about secondary damages such as network cloning, impersonation, and smishing due to the KT hacking incident." She added, "Compared to SK Telecom, which took comprehensive customer protection measures such as USIM replacement after experiencing a similar hacking incident in the past, KT’s response has been excessively passive. If requests for USIM replacement surge as the situation worsens, it could cause significant inconvenience for subscribers."