- SK Telecom confirmed that he suffers a malware infection on a Saturday night
- The attackers tried to steal USIM data
- Police and government have been notified
SK Telecom, the largest telecommunications provider in South Korea, suffered a recently malware infection, through which the threat actors tried to obtain information from Usim customers.
The attack occurred in mid -April 2025, at night between Saturday and Sunday, when most employees were out during the weekend.
The company’s IT team saw the intrusion and moved quickly to isolate the affected final points and prevent more data from being stolen. In the morning, SK Telecom notified the relevant authorities and began an investigation to determine exactly what happened and what was stolen.
Github not affected
Until now, no data appeared on the dark website and no one was responsible for the attack.
A USIM (universal subscriber identity module) is the successor of the previous SIM card. It is used in 3G, 4G and 5G mobile networks and is found in most cell connectivity devices.
In essence, an authentic Usim the identity of the device in a network, stores subscriber data (identity of international mobile subscribers, authentication keys, contacts and, sometimes, text messages), figure the information that passes and allows safe access to mobile services such as calls, data or texts.
A cybercriminal could use the data to close the SIM, track the location of people, avoid the security of applications or listen to communications.
In other words, this was a fairly dangerous attack. That is why the company strengthened Usim swaps blocks and abnormal authentication attempts. In addition, he said he would immediately suspend the service for accounts linked to suspicious activities.
SK Telecom is the largest telecommunications supplier in South Korea, which serves about 34 million subscribers (approximately 49% of the market). The rest is mainly divided between KT and LG U+.
It offers mobile services, internet and IPTV, AI and cloud services, IoT solutions, smart factory car and connected cars, quantum cryptography communication and more. It was one of the first companies in the world to launch Commercial 5G, in 2019.
Through Bleepingcomputer
