Finance

SK Telecom shares plunge after data breach due to cyberattack

Published by Global Banking & Finance Review

Posted on April 28, 2025

2 min read

· Last updated: January 24, 2026

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SK Telecom shares plunge after data breach due to cyberattack
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SK Telecom Shares Tumble Following Data Breach Incident

SEOUL (Reuters) -SK Telecom shares fell as much as 8.5% on Monday to hit their lowest level since August last year, after South Korea's biggest mobile carrier disclosed it suffered a leak of customer data earlier this month caused by a cyberattack.

The company said in a statement it would take full responsibility for any harm caused as a result of the breach that was detected on April 18. It described the incident as a large-scale leak of data due to malware, without providing more details.

SK Telecom also said it would start offering free universal subscriber identity module (USIM) replacements to all 23 million users for free at more than 2,600 retail stores nationwide from Monday following the cybersecurity breach.

SK Telecom also urged customers to sign up for its USIM Protection Service, which it said provided the same level of prevention as replacing a USIM card.

About 5.54 million people had signed up for the service, accounting for nearly a quarter of SK Telecom's 23 million subscribers as of Sunday, according to the company.

SK Telecom shares closed down 6.7%, posting the biggest daily drop since March 2020, versus the benchmark KOSPI's 0.1% rise.

(Reporting by Heekyong Yang and Jihoon LeeEditing by Ed Davies)

Key Takeaways

  • SK Telecom shares dropped 8.5% due to a data breach.
  • The breach was caused by a cyberattack involving malware.
  • Free USIM replacements are offered to 23 million users.
  • 5.54 million users have signed up for USIM Protection Service.
  • SK Telecom shares saw the biggest drop since March 2020.

Frequently Asked Questions

What is the main topic?
The main topic is the data breach at SK Telecom and its impact on the company's shares.
What caused the data breach?
The data breach was caused by a cyberattack involving malware.
How is SK Telecom responding to the breach?
SK Telecom is offering free USIM replacements to all affected customers.

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