Vulnerabilities / Threats
5/22/2014
11:40 AM
Connect Directly
RSS
E-Mail
50%
50%

Flaws In EMV Chip And PIN Undercut Security

Weaknesses in the EMV protocol and implementations create vulnerabilities that could be exploited via POS malware and man-in-the-middle attacks.

10 Ways To Fight Digital Theft & Fraud
10 Ways To Fight Digital Theft & Fraud
(Click image for larger view and slideshow.)

More than one year after receiving warnings from security researchers that there are serious flaws in the EMV protocol used to authenticate credit and debit card transactions in 80 countries around the world, card issuers and ATM manufacturers have failed to patch all related flaws.

Cambridge University computer security researchers sounded that warning this week in a presentation at the IEEE Symposium on Privacy and Security in San Jose, Calif., in which they detailed two major problems with the EuroPay, MasterCard, and Visa (EMV) standard now used to secure more than 1.6 billion cards worldwide.

The researchers said they began exploring EMV security, often referred to as chip and PIN -- "in layman's terms, the chip protects against card counterfeiting, and the PIN against stolen card abuse," they explained in a related research paper -- after British bank HSBC refused to refund a series of transactions to a customer based in Malta named Mr. Gambin. During related disputed-transaction negotiations, HSBC shared detailed ATM log data with Gambin, which included the date, time, as well as an "unpredictable number" (UN), or "nonce," generated by the ATM to validate the transactions.

[Are you an eBay user? Change your password now. Read 7 Facts: eBay Fumbles Password Reset Warning.]

Reviewing the unpredictable number, however, the researchers found that it was, in fact, often predictable. "Some EMV implementers have merely used counters, timestamps or home-grown algorithms to supply this nonce," they said. "This exposes them to a 'pre-play' attack, which is indistinguishable from card cloning from the standpoint of the logs available to the card-issuing bank, and [which] can be carried out even if it is impossible to clone a card physically."

In some cases, obtaining a legitimate ATM nonce on which to base an attack would also be easy. According to the researchers, for example, the UN is printed on all receipts generated in Italy.

Digging further, the researchers also spotted a deeper flaw in the protocol that attackers could use to compromise transactions, even when an ATM generated a cryptographically strong random number. That flaw is due to the ability of attackers to intercept the unpredictable number via a man-in-the-middle attack and replace it with a different pre-computed one, which would likely pass muster with the authorizing bank. Such an attack could be executed via malware installed on POS devices, even if those devices include tamper-resistant EMV modules.

A Visa spokesman did not immediately respond to an emailed request for comment about the researchers' findings.

To date, some of the random-number-generator flaws spotted by the researchers have now been patched. But the EMV alliance has yet to address the deeper flaw in the protocol itself. "The banks appear to have ignored this, perhaps reasoning that it is difficult to scale up an attack that involves access to specific physical cards and also the installation of malware or wiretaps on specific terminals," the researchers said. "We disagree. The Target compromise shows that criminals can deploy malware on merchant terminals widely and exploit it to earn serious money."

The researchers added that they know of at least one "likely case" of a related skimming attack in the wild, and warned that "the spread of ATM and POS malware is making it ever more of a threat."

In the wake of the Target breach, which occurred after attackers managed to sneak malware

Next Page

Mathew Schwartz is a freelance writer, editor, and photographer, as well the InformationWeek information security reporter. View Full Bio

Previous
1 of 2
Next
Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
Partner Perspectives
What's This?
In a digital world inundated with advanced security threats, Intel Security seeks to transform how we live and work to keep our information secure. Through hardware and software development, Intel Security delivers robust solutions that integrate security into every layer of every digital device. In combining the security expertise of McAfee with the innovation, performance, and trust of Intel, this vision becomes a reality.

As we rely on technology to enhance our everyday and business life, we must too consider the security of the intellectual property and confidential data that is housed on these devices. As we increase the number of devices we use, we increase the number of gateways and opportunity for security threats. Intel Security takes the “security connected” approach to ensure that every device is secure, and that all security solutions are seamlessly integrated.
Featured Writers
White Papers
Cartoon
Current Issue
Dark Reading's October Tech Digest
Fast data analysis can stymie attacks and strengthen enterprise security. Does your team have the data smarts?
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2013-7407
Published: 2014-10-22
Cross-site request forgery (CSRF) vulnerability in the MRBS module for Drupal allows remote attackers to hijack the authentication of unspecified victims via unknown vectors.

CVE-2014-3675
Published: 2014-10-22
Shim allows remote attackers to cause a denial of service (out-of-bounds read) via a crafted DHCPv6 packet.

CVE-2014-3676
Published: 2014-10-22
Heap-based buffer overflow in Shim allows remote attackers to execute arbitrary code via a crafted IPv6 address, related to the "tftp:// DHCPv6 boot option."

CVE-2014-3677
Published: 2014-10-22
Unspecified vulnerability in Shim might allow attackers to execute arbitrary code via a crafted MOK list, which triggers memory corruption.

CVE-2014-4448
Published: 2014-10-22
House Arrest in Apple iOS before 8.1 relies on the hardware UID for its encryption key, which makes it easier for physically proximate attackers to obtain sensitive information from a Documents directory by obtaining this UID.

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Follow Dark Reading editors into the field as they talk with noted experts from the security world.