Last week saw the biggest credit card data breach for a while, with around 1.5 million card numbers being stolen by organised crime from processor Global Payments [updated figures per Global Payments investor conference call, Apr 2nd].
So now there will be another few rounds of debate about how to harden these cardholder databases against criminal infiltration, and whether or not the processor was PCI-DSS compliant. Meanwhile, stolen card numbers can be replayed with impugnity and all the hapless customers can do is monitor their accounts for suspicious activity — which can occur years later.
These days, the main use for stolen payment card data is Card Not Present (CNP) fraud. Traditional “carding” — where data stolen by skimming is duplicated onto blank mag stripe cards to fool POS terminals or ATMs — has been throttled in most places by Chip-and-PIN, leaving CNP as organised crime’s preferred modus operandi. CNP fraud now makes up three quarters of all card fraud in markets like Australia, and is growing at 40-50% p.a.
All card fraud exploits a specific weakness in the Four Party card settlement system shown below. The model is decades old, and remains the foundation of internationally interoperable cards. In a triumph of technology neutrality, the four party arrangement was unchanged by the advent of e-commerce. The one problem with the system is that merchants accepting card numbers may be vulnerable to stolen numbers. Magnetic stripe terminals and Internet servers are unable to tell original cardholder data from copies replayed by fraudsters.
The most important improvment to the payments system was and still is to make card numbers non-replayable. Chip-and-PIN stops carding thanks to cryptographic processes implemented in hardware (the chip) where they cannot be tampered with, and where the secret keys that criminals would need are inaccessible. In essence, a Chip-and-PIN card encrypts customer data within the secure chip (actually, digitally signs it) using keys that never leave the confines of the integrated circuit. Even if a criminal obtains the card holder data, they are unable to apply the additional cryptographic transformations to create legible EMV card-present transactions. This is how Chip-and-PIN stemmed skimming and carding.
CNP fraud is just online carding, fuelled by industrial scale theft of customer records by organised crime, like the recent Global Payments episode. While the PCI-DSS regime reduces accidental losses and amateur attacks, it remains powerless to stop determined criminals, let alone corrupt insiders. When card numbers are available by the tens of millions, and worth several dollars each ($25 or more for platinum cards) truly nothing can stop them from being purloined.
The best way to tackle CNP fraud is to leverage the same hardware based cryptography that prevents skimming and carding.
Lockstep Technologies has developed and proven such a solution. Our award winning Stepwise digitally signs CNP transactions within an EMV chip, rendering card details sent to the merchant non-replayable. The merchant server checks a Stepwise CNP transaction using standard public key libraries; a valid Stepwise transaction can only have come from a genuine Chip-and-PIN card under the control of its holder.
All serious transaction and payments systems use hardware cryptography. The classic examples include mobile telephones’ SIM cards, EMV chips, the Hardware Security Modules mandated by financial regulators in all ATMs, and the “secure elements” of NFC devices. With well designed hardware security, we gain a robust upper hand in the cybercrime arms race. So let’s stop struggling with flabby distracting systems like 3D Secure, and let’s stop pretending that PCI-DSS audits will stop organised crime getting hold of card numbers by the million. Instead, let’s kill two birds with one stone and use chips to secure both card present and CNP transactions.
Stepwise creates uniquely secure, fast and easy-to-use CNP payments. It has zero impact on the security certifications of digital signature capable EMV chips, and zero impact on existing four party card processing arrangements.
For more details, please see https://lockstep.com.au/technologies/stepwise.