Due to a data leak, data from users of the Mastercard bonus program "Priceless Specials" from Germany have at times appeared in an online forum. A spreadsheet file includes, among other things, customer names and e-mail addresses. Next to it were the first two and the last four numbers of the Mastercard card numbers and in some cases the address and phone number of the credit card users.
The platform of the bonus program had been closed as a precaution, said Mastercard. "We take privacy very seriously and are investigating this problem with great effort." At the same time, the company said it had no connection with MasterCard's payment network.
A sample check found correct data among the more than 89,400 entries. At the same time, the name "Max Mustermann" appeared several times. The list also included information on whether users had subscribed to a newsletter and SMS notifications. The date of birth and the dates in the "Customer since" column were unrecognizable in the table.
Particularly dangerous to such data leaks is the ability for criminals to fabricate emails that look deceptively real to get passwords and other information from users.
Mastercard introduced "Priceless Specials" at the beginning of last year in Germany. With the free program you get for bonus points, which can be exchanged for rewards.