Seoul: A joint government-private investigation team looking into SK Telecom Co.'s recent large-scale data breach has extended its probe to the servers of other major mobile carriers and platform companies, but found no signs they have been compromised, industry sources said Monday.
According to Yonhap News Agency, the team initially requested local telecommunications and platform companies to conduct their own cybersecurity inspections. However, last week, the team shifted its approach and carried out on-site inspections at telecom carriers KT Corp. and LG Uplus Corp., along with four major platform companies-Naver Corp., Kakao Corp., Coupang Inc., and Baedal Minjok.
The investigation was broadened due to growing concerns that hackers employing BPFDoor malware variants might have targeted other Korean tech firms. Despite these concerns, investigators reported that no traces of hacking activity have been discovered on the servers of any of the six companies inspected.
During a media briefing last week, the investigation team disclosed interim findings, revealing that 25 malware variants had been identified on 23 servers belonging to SK Telecom. These included 24 variants of the BPFDoor malware and one variant of WebCell.
Two of the affected servers had been used for temporary storage of personal data, such as names, birthdates, phone numbers, email addresses, and international mobile equipment identity (IMEI) data. The IMEI is a unique identifier for each device on a network and could potentially be exploited in financial transactions.