Companies such as Naver, Kakao, NHN, NCSOFT, and Netmarble have raised their security alert levels due to the 'SK Telecom hacking' incident. These corporations have recently issued internal notices to all employees recommending the 'replacement of SK Telecom USIM (Subscriber Identity Module).'
Earlier, Samsung, Hyundai Motor, POSCO, Hanwha, and HD Hyundai had advised their employees to replace their USIMs. The SK Telecom hacking phobia is spreading across the domestic industry.
According to the IT industry on the 28th, Naver advised on the 25th in an internal notice that 'employees using SK Telecom should join the USIM protection service and replace their USIMs if possible.' Kakao, NHN, NCSOFT, and Netmarble also issued an internal notice that morning, informing employees about the details of the SK Telecom hacking incident and methods for enhancing security.
Earlier, Samsung Electronics directed its executives on the 23rd to 'immediately replace the USIM if they are using SK Telecom.' Other major subsidiaries within Samsung also recommended USIM replacement to their employees between the 24th and the 25th. HD Hyundai (on the 22nd), Hanwha (on the 25th), and Hyundai Motor (on the 28th) also urged their employees to be cautious.
An IT industry official noted, 'In a situation where handling company tasks via smartphones is common, corporations are advising their employees to replace their SK Telecom USIMs to prevent any potential information leaks,' adding, 'This is intended to raise awareness for security enhancement.'
SK Telecom recognized signs of hacking on the 18th and reported the related facts to the Korea Internet & Security Agency (KISA) at 4:46 p.m. on the 20th, approximately 45 hours later. SK Telecom claimed that, so far, only USIM-related information has shown signs of being leaked, while personal information such as address and resident registration numbers have not been stolen. They also stated that there have been no cases of misuse of the leaked information discovered thus far.
However, security experts express concerns that if the stolen USIM-related information is misused, it could lead to the creation of cloned smartphones. According to security industry analysis, information such as the International Mobile Subscriber Identity (IMSI), International Mobile Equipment Identity (IMEI), and USIM authentication key could potentially be used in 'SIM swapping' crimes, which poses a risk of secondary damage.
The Financial Supervisory Service (FSS) sent an official document to financial companies on the 24th, warning that hackers might try to bypass mobile phone authentication through USIM duplication and engage in fraudulent financial transactions. After the FSS communicated its precautions, some insurance companies halted SK Telecom certifications. KB Life proactively took action on the 25th, and NH Nonghyup Life plans to implement related measures starting as early as the 29th. Credit card companies, including Samsung, KB Kookmin, and Lotte, also posted notices on their websites recommending USIM replacement to prevent financial damages for SK Telecom users.