"Within the last 36 hours, we learned that unauthorized third parties obtained the e-mail addresses of some of our CurrentC pilot program participants and individuals who had expressed interest in the app," Linda Walsh, a spokeswoman for Merchant Customer Exchange, told ABC News in a statement.
"Many of these email addresses are dummy accounts used for testing purposes only. The CurrentC app itself was not affected," Walsh said.
She added that the breach was communicated to the app's test users and to the group's merchant partners, among them Walmart, Target and 7-Eleven.
The mobile payments solution was quietly announced in September, but was thrust into the spotlight earlier this week when it was reported that some retailers involved in the development of CurrentC had taken measures to disable or alter their NFC readers so Apple Pay, a competitor, cannot be used.
A consortium of retailers, including Best Buy, 7-Eleven and Target, are members of the Merchant Customer Exchange, which announced last month it is working on the mobile wallet, which is expected to be a direct competitor to Apple Pay.
Before the hack was confirmed, Dekkers Davidson, CEO of the Merchant Customer Exchange, posted a blog today offering new details on CurrentC, user security and why the mobile wallet and Apple Pay will never compete in the same store.
Blocking Apple Pay
Davidson's message is clear: Retailers are either in or they're out.
"When merchants choose to work with MCX, they choose to do so exclusively and we’re proud of the long list of merchants who have partnered with us," Davidson wrote. "Importantly, if a merchant decides to stop working with MCX, there are no fines."
While Apple Pay promises to keep your data private, CurrentC is all about letting merchants have more information about what their customers are doing.
Davidson said customers and merchants will be able "to make informed decisions regarding how information can be shared" via a privacy dashboard. MCX may see "limited information" on prescription purchases, such as location and transaction amount, but will "adhere to strict rules regarding the privacy of consumers’ information."
CurrentC will store financial information in a cloud vault, according to a release detailing the service. A "token placeholder" will be used to make transaction, ensuring a user's sensitive financial data isn't exposed.
MCX said the mobile wallet will offer "merchant loyalty programs and instant coupon savings, all stored on the phone and available right at the point-of-sale."