The breach, detected on April 18, involved malicious code that compromised unique identification numbers tied to customer SIM cards, the company said.
SK Telecom, which serves roughly 23 million subscribers and hosts an additional 1.87 million users through budget carriers on its network, said it has about one million SIM cards in stock and plans to secure another five million by the end of next month.
Analysts warned that shortages and service disruptions could arise as the company moves to replace SIM cards for as many as 25 million customers.
Customers can obtain replacement SIM cards at T World stores or airport roaming centers. Anticipating heavy demand, the company urged customers to make online reservations in advance to avoid long waits.
“We expect considerable inconvenience if customers rush to stores simultaneously,” an SK Telecom spokesperson said.
In the days before launching the replacement program, SK Telecom had encouraged users to sign up for its SIM protection service, developed in cooperation with the Seoul Metropolitan Police Agency’s cybercrime unit. The service is designed to prevent unauthorized access even if SIM information is stolen or duplicated.
Following the breach, SK Telecom said it had raised its fraud detection system to its highest alert level to block suspicious authentication attempts. The company added that no instances of actual financial or identity theft had been reported to date. Investigations by the Korea Internet & Security Agency and police authorities are ongoing.
Despite these measures, concerns continue to mount across sectors.
The Financial Supervisory Service has advised banks and other institutions to consider using additional authentication methods beyond mobile verification. Several insurance companies have temporarily suspended mobile-based authentication services linked to SK Telecom users.
On Sunday, South Korea’s Acting President and Prime Minister Han Duck-soo instructed the Ministry of Science and ICT to conduct a thorough review of SK Telecom’s response to the incident.
“We sincerely apologize for the inconvenience caused to our customers due to this cyber intrusion,” the company said in a statement. “We will do our utmost to address customer concerns and resolve this incident as quickly as possible.”
reporter
Kim Dong-young
davekim0807@ajupress.com
Copyright ⓒ Aju Press All rights reserved.
View more comments