Voice phishing cases detected by major banks double in 2025

ATMs operated by major banks are seen at a location in Seoul, Oct. 7, as victims of recent personal data breaches in the banking sector move toward filing class-action lawsuits. Yonhap
The number of voice phishing transactions confirmed as fraud after being flagged by monitoring systems at major commercial banks doubled last year from a year earlier, data showed Sunday.
According to the data submitted by the Financial Supervisory Service to Rep. Park Seong-hoon of the People Power Party, the five major banks — KB Kookmin Bank, Shinhan Bank, Hana Bank, Woori Bank and NH Nonghyup Bank — detected 8,760 such transactions through their fraud detection systems (FDS) in 2025 and subsequently confirmed them as actual fraud after taking temporary measures to suspend them.
The figure more than doubled from 4,343 cases in 2024.
An FDS is a technical system that monitors transactions, user activity and other data in real time to identify and flag suspicious behavior.
The banks' FDS flagged 1.11 million suspected voice phishing transactions last year, up 39.9 percent from 796,000 in 2024.
Of those, the banks took temporary measures against 157,000 transactions in 2025, up from 125,000 in 2024.
Recently, Korean financial institutions are stepping up efforts to strengthen their cybersecurity measures as a series of cyberattacks have exposed the personal information of about 100,000 people across the industry, including email addresses, names and phone numbers.