KT internet installer leaks customer data; complaint closed
A KT internet installation technician leaked customers' personal information. Even after receiving a report, KT closed the complaint by blaming voice phishing without verifying the facts.
Key facts
- Affected organization
- KT
- Incident type
- Data breach
- Occurred / detected
- Not confirmed
- Scale of damage
- Customer personal information
- Cause / method
- Leak of customer personal information by an internet installation technician
- Location
- South Korea
If your data was exposed
- Don’t tap links in texts, calls or emails that mention this incident and offer compensation, refunds or breach checks. Check directly on the organization’s official website or app.
- If you’ve suffered harm, report it. Call 118 (no area code) for privacy violations, contact the police for financial losses, and apply for dispute mediation to seek compensation.Personal Information Infringement Report Center ↗Korean National Police Agency cybercrime report ↗Personal Information Dispute Mediation Committee ↗
Timeline
- The leak of customer information by a KT internet installation technician and problems with the response after it was reported came to light.
- It emerged that KT had closed the complaint by blaming voice phishing without verifying the facts.
2 related reports
Other incidents at KT
Illegal femtocell breach at KT exposes personal data of 16,647 people
16.6KImpact: Personal information of 16,647 people exposed; 368 people incurred approximately KRW 240 million in unauthorized mobile micropayment charges
A breach at KT involving illegal miniature base stations known as femtocells exposed the personal information of 16,647 people, while 368 people suffered approximately KRW 240 million in unauthorized mobile micropayment charges. Investigators confirmed access to the internal network using cloned certificates and management failures, and KT announced a program waiving early termination fees and providing compensation. The Personal Information Protection Commission (PIPC) announced an administrative fine of KRW 53.979 billion and a criminal referral over obstruction of its investigation in July 2026, with further inquiries and criminal investigations still ongoing in November.
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Impact: 43 servers confirmed infected with malware
Between March and July 2024, KT discovered 43 servers infected with malware including BPFDoor and handled them on its own without reporting. In a company-wide server inspection in September 2025, it found traces of intrusion and suspicious signs and reported them to the Korea Internet & Security Agency. A government investigation revealed the malware infections and the failure to report; KT apologized and announced plans to build an integrated monitoring system. Controversy continued afterward over log deletion and the submission of materials.
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Related reports: 3 · last report →
The summary and key facts are written by AI from related reports and may contain errors. Check the original articles and the organization’s official statements for accurate details.