SK Telecom Reports Major SIM Data Breach Affecting Customer Information

SK Telecom Subscribers’ Personal Information Leaked in Massive Hack

Photo: SK Telecom's chief executive officer Yu Yeong-sang issues a public apology for the hacking attack. Credit: SK Telecom.On April 22, SK Telecom SK 텔레콤 disclosed that personal information for a significant number of subscribers had been leaked in a cybersecurity attack. The leaked personal information included the extremely sensitive USIM authentication keys used for individual access to apps, websites, and payment systems.With more than 23m…

SK Telecom Reports Major SIM Data Breach Affecting Customer Information

SK Telecom has disclosed a data breach affecting customer SIM-related information, discovered on April 19, 2025. The telecommunications provider detected malware on its systems at approximately 11:00 PM and took immediate action to remove the malicious software and isolate the affected device. The incident follows a series of SIM-related security challenges that have plagued the telecommunications industry in recent years. The company formally r…