South Korea's privacy regulator has fined KT (KRX:030200) 53.98 billion won due to a data breach, according to a Thursday release.
The telecommunications company neglected to properly secure its femtocell system, which allowed hackers unauthorized access to its mobile network, according to the Personal Information Protection Commission (PIPC).
The breach, which occurred in 2024 and 2025, included phone numbers and identification numbers of 16,647 users, which were used for unauthorized transactions.
Financial damage related to the breach reached 240 million won, impacting 368 people.
The PIPC also found lapses on KT's response to the breach, including not reporting the incident, deleting server logs and submitting false data.
The regulator ordered the telecom company to adopt corrective efforts following the breach.
Shares of the company fell more than 2% in recent trade.