Credit card users from four major banks have complained they have been hit with fraudulent charges.
Customers of DBS, Citibank, UOB and OCBC were asked to pay money to Taiwan-based Neweb Technologies.
Some shared their experiences on online forum Hardware Zone, saying they were first alerted to the charges by text messages and had cancelled their credit cards. One told The Straits Times that he was asked to pay the equivalent of around $48 in Taiwanese currency.
All four banks said customers would not be liable to pay the unauthorised charges.
Citibank Singapore said on Monday that it is aware of unauthorised credit card transaction activities from a merchant in Taiwan. It first received calls about the problem on Saturday and has taken steps to block transaction activity with Neweb Technologies. Affected customers will not be liable for unauthorised charges incurred over the last three days with this merchant, the bank said, adding that there was no breach of any Citibank systems.
UOB has also blocked transactions with Neweb Technologies and will be reimbursing customers for any unauthorised transactions made.
DBS said that it is helping customers who might be affected and will replace their cards promptly to minimise any inconvenience.
OCBC said that it was aware of the fraud and was alerting customers who might be affected. All unauthorised transactions will be cancelled. The bank said it sends out SMS alerts to customers when transactions above a certain limit are made.
According to Internet-based news outlet Taiwan Today, Neweb Technologies is a leading third-party payment processor for online transactions in Tauwan. In 2012, it teamed up with Chinese online portal 360buy.com to sell more Taiwan-made products to the China market.