It was confirmed that 17,551 customer personal data records were leaked from an external developer that carried out Woori Bank's NFT platform construction project.

On July 3, the financial sector said Woori Bank informed customers of the personal data leak by text message.

According to Woori Bank's notice, the incident occurred when personal data that the external developer had kept on its own was leaked due to an employee's mistake at the company.

The leaked personal data were user nicknames and linked identification information (CI). The user nickname is not a member ID or login account information, and the CI is a value used to identify an individual online.

Woori Bank explained that after becoming aware of the leak on June 30, it blocked access to related information through the developer. The developer was reported to have filed a report with the Personal Information Protection Commission and posted a notice about the matter on its website.

Woori Bank said it has determined that, so far, there have been no cases of the leaked information spreading or being misused online or offline. It nevertheless advised customers to be cautious about receiving calls of unclear origin or clicking URL links in text messages.

Woori Bank said it is applying a separate abnormal financial transaction detection system to protect customers. It also plans to conduct a full inspection of the developer's personal data management status and immediately correct any shortcomings.

Woori Bank CEO Jin-wan Jeong (정진완) apologised in a text message sent to customers, saying, "We will use this incident as an opportunity to conduct a full inspection of the developer's personal data management status and immediately correct any shortcomings."

He added, "We will do our utmost to prevent a recurrence by strengthening Woori Bank's personal data protection system," and promised, "If customer damage occurs as a result of this leak, we will verify it as quickly as possible and provide compensation."