SK Telecom CEO acknowledges worst telecom hack in history

SK Telecom CEO Yoo Young-sang on Tuesday acknowledged that the recent SIM card data breach is the worst hacking incident in South Korea’s telecommunications history. Testifying before the National Assembly’s Science, ICT, Broadcasting and Communications Committee, Yoo said he “agreed with the assessment” and added that the company is preparing for a worst-case scenario in which the personal data of all 25 million customers may have been compromised.

Lawmakers grilled Yoo over issues such as the potential for SIM card cloning, delayed response measures, and compensation plans. In response to concerns that cloned SIM cards could facilitate financial fraud, Yoo explained that while SIM duplication is technically possible, “SK Telecom defends against this with an abnormal authentication blocking system.”

When asked where the blame for the breach lies, Yoo acknowledged, “It lies with SK Telecom.” However, when pressed on whether the company would waive early termination fees for customers canceling their contracts due to the breach, he stopped short of committing, saying only that “a comprehensive review is needed.”

Yoo also announced new measures aimed at protecting vulnerable groups, stating that SK Telecom is considering automatically enrolling these customers in SIM protection services and making it easier for them to reserve SIM card replacements. He further pledged full compensation for any customers harmed by SIM hacking, including those not enrolled in the protection service. The committee also summoned SK Group Chairman Chey Tae-won and Science and ICT Minister Yoo Sang-jim as additional witnesses.

Public trust in SK Telecom has plummeted, with about 70,000 subscribers leaving the service just two days after the breach was disclosed. Police have expanded the special investigation team to handle the case and launched a full-scale probe.

To reassure users, SK Telecom said it plans to boost sign-ups for its SIM protection service and secure an additional 10 million SIM cards by June. The company expects that replacing SIM cards for its entire subscriber base will take at least three months.


남혜정 기자 namduck2@donga.com