SK Telecom Enrolls Over 24 Million Users in USIM Protection After Cyberattack

SEOUL — SK Telecom Co., South Korea's largest mobile carrier, announced Tuesday that more than 24 million customers have been automatically enrolled in its USIM protection service following a recent cyberattack that compromised user data.

As of 9 a.m., approximately 24.1 million subscribers were signed up for the service, the company said in its daily briefing. The USIM protection initiative aims to defend users against illegal financial activities, providing a safeguard equivalent to physically replacing the USIM chip.

The company began automatically enrolling users into the service last Friday in response to the breach. So far, about 1.04 million customers have replaced their USIM cards, while an additional 7.8 million have made reservations for new ones. SK Telecom has been offering the replacements free of charge.

“We apologize as many of our users are still waiting to replace their USIM cards,” said Kim Hee-sup, head of SK Telecom's Public Relations Center, adding that the company is working to resolve the shortage “as soon as possible.”

SK Telecom detected signs of a large-scale data leak involving USIM information after a cyberattack on April 18. The company serves nearly half of South Korea’s population of 52 million.

In line with government directives, SK Telecom suspended new subscriber registrations nationwide on Monday until the USIM shortage is resolved and additional security measures are implemented.