KT — Cyber Attacks, Breaches & Threat Activity

Threat entity extracted from intelligence sources

Frequency
16
occurrences
First Seen
November 3, 2025
Last Seen
July 13, 2026

KT (Korea Telecom) is South Korea's largest telecom operator, providing fixed-line, mobile, internet, and digital services.

Overview

KT (Korea Telecom) is South Korea's largest telecom operator, providing fixed-line, mobile, internet, and digital services. In cybersecurity contexts, KT has recently become the focus of police investigations related to a data breach and an alleged disposal of servers, contributing to leadership turmoil in Korea's telecom sector following notable hacking incidents. These developments highlight the sensitivity of KT's data handling and the broader security challenges facing major carriers in the region.

Related Threat Clusters

  • SK Telecom Malware Breach Affects 27 Million Customers Over Three Years

    SK Telecom, South Korea's largest mobile network operator, reported a malware breach that lasted nearly three years, impacting approximately 26.95 million customers. The breach, detected on April 19, 2025, involved…

    2 articles · Updated July 13, 2026
  • South Korea Implements Universal Basic Mobile Data Access Amid Security Concerns

    On April 11, 2026, South Korea launched a universal basic mobile data access scheme to ensure all citizens have access to online services. This initiative was prompted by recent security lapses among the country's…

    2 articles · Updated April 11, 2026
  • Coupang Data Breach Affects 33.7 Million Users

    Coupang experienced a significant data breach, exposing personal information of approximately 33.7 million users. The leaked data includes names and addresses, prompting the company to warn users about potential scams…

    94 articles · Updated November 29, 2025
  • Government Waives Fees for KT Subscribers Due to Eavesdropping Risks

    The South Korean government has mandated fee waivers for all KT subscribers following an investigation that revealed a security flaw in KT's system, exposing users to potential eavesdropping. This decision affects all…

    2 articles · Updated December 30, 2025
  • Kyowon Group Confirms Cyberattack Disrupting Services

    Kyowon Group has confirmed a cyberattack that has affected multiple systems, leading to service disruptions. The company, which has millions of members across its affiliates, detected signs of the attack on January 11…

    3 articles · Updated January 12, 2026
  • Police Investigate KT for Evidence Destruction in Data Breach Case

    Police raided KT offices as part of an investigation into a data breach. The focus is on whether KT intentionally destroyed evidence related to a hacking incident, following reports from U.S. media.

    4 articles · Updated November 20, 2025
  • State-Level Cyber Espionage Targeting KT Telecom in South Korea

    A report by Rethink Technology Research indicates that a cyberattack on KT, South Korea's leading telecom operator, may involve state-level cyber espionage. The report, published on December 10, 2025, analyzes the…

    1 article · Updated December 17, 2025
  • KT Breach Investigation Reveals Malware Infections in 94 Servers

    The Ministry of Science and ICT announced the findings of a public-private investigation into a breach at KT. Out of 33,000 servers inspected, 94 were infected with 103 types of malware, including BPFDoor and Rootkit,…

    1 article · Updated December 29, 2025
  • KT Hacking Incident Leads to Government Action on User Fees

    The South Korean government is urging KT, the nation's second-largest mobile carrier, to waive contract termination fees for users affected by a security breach. The incident, which began in 2024 when malware was…

    2 articles · Updated December 29, 2025
  • Police Investigate KT for Evidence Destruction in Data Breach Case

    Police raided KT offices as part of an investigation into an alleged data breach. The focus is on whether KT intentionally destroyed evidence related to a hacking incident following a report by U.S. media.

    2 articles · Updated November 20, 2025

Recent Intelligence Reports

  • Telecoms step up cybersecurity spending after breaches — Koreatimes.Co.Kr · July 13, 2026
  • South Korea introduces universal basic mobile data access — News.Ycombinator · April 11, 2026
  • South Korea introduces universal basic mobile data access — Theregister · April 10, 2026
  • KT, LG Uplus face lingering fallout over hacking incidents — Koreatimes.Co.Kr · February 27, 2026
  • Kyowon Group Confirms Cyberattack as Multiple Systems Go Offline — Thecyberexpress · January 12, 2026
  • [Exclusive] Kyowon Group Also Hit by Hacking Incident: "Still Investigating Possible ... — Cm.Asiae.Co.Kr · January 11, 2026
  • Government Recommends KT Cancellation Fee Waivers Amid Eavesdropping Risks — Chosun · December 30, 2025
  • Gov't Urges KT to Waive User Cancellation Fees after Security Breach — World.Kbs.Co.Kr · December 29, 2025

CVSS v3.1 Breakdown