Payment data from about 130,000 accounts for users of a Line Pay Corp. smartphone app both in Japan and abroad was available on the internet for more than two months until late November, the company has said.
The app service is operated by major messaging app Line Corp.
Line Pay said Monday the information accidentally uploaded by a group firm, which was viewable between Sept. 12 and Nov. 24, included payment amounts, dates and times during a promotional campaign held from December 2020 to April this year, but did not include data such as user names, addresses or credit card numbers.
Although no damage has been reported so far due to the information leak, it may have been possible to identify users through special analysis, Line Pay said.
The company said it has confirmed 11 instances in which the information was accessed externally and warned users they could receive suspicious messages from potential fraudsters.
"We apologize deeply for causing great trouble and concern," the firm said in a statement.
Line Pay allows users to send money to each other, make online purchases or pay at shops and restaurants.