Seoul: The U.S. Forces Korea (USFK) has issued a safety advisory urging its troops and employees who are subscribers of SK Telecom Co. to take precautionary actions following a significant cyberattack on the mobile carrier, which is South Korea's largest.

According to Yonhap News Agency, USFK updated its website with a post titled "SK Telecom Breach Cyber Threat Advisory," highlighting the potential risks associated with the hacking incident. The advisory recommends that SK Telecom users replace their universal subscriber identity module (USIM) chips and enroll in protective services to safeguard their personal information.

SK Telecom, which serves approximately half of South Korea's 50 million residents, identified the cyberattack on April 18. The company noted evidence of a large-scale leak of customers' USIM data, prompting concerns about data security and privacy.

In response to the breach, Seoul's defense ministry has also directed military units to develop strategies to assist soldiers in replacing their USIM chips and registering for the mobile carrier's protective services to mitigate potential risks.