SK Telecom was found to have had 9.7 gigabytes (GB) of information leaked due to a hacking attack. In terms of document files, this amounts to 9,000 books of 300 pages each.
According to the data submitted by SK Telecom to Rep. Choi Min-hee of the Democratic Party of Korea, chairperson of the National Assembly's Science, Technology, Information, Broadcasting, and Communications Committee, the external data leaked due to the hacking attack included core information on the Universal Subscriber Identity Module (USIM). The company first detected abnormal data movement at approximately 6:09 p.m. on the 18th at its security monitoring center. At that time, data amounting to 9.7GB was transmitted externally.
On the night of the 18th at approximately 11:20 p.m., SK Telecom discovered malware in its billing analysis equipment (WCDR). Around 11:40 p.m. on the 19th, suspicious circumstances regarding data leakage were also confirmed in the voice authentication equipment (HSS).
The National Assembly's Science, Technology, Information, Broadcasting, and Communications Committee will conduct a thorough examination of SK Telecom regarding this hacking incident during a hearing on the 30th. Rep. Choi noted that "SK Telecom must quickly secure more USIMs and take more proactive measures, such as in package delivery, and should immediately implement practical compensation measures for customers wishing to change their numbers, including waiving penalty fees."