Mastercard and Visa have alerted financial institutions about another serious data breach at a payment processor, Wired reports. The breach, like the massive fraud unveiled at Heartland Payment Systems last month, is believed to have occurred through malicious software. The credit card issuers are refusing to name the processor involved because it has yet to go public with the breach.
The information stolen is believed to be credit card numbers and expiration dates from card-not-present transactions, which limits the amount of fraud that can be committed. The alerts do not state how many customers' details were stolen, although the announcement says the malicious code was on the processor's systems from February 2008 until last month.