Making Code Harder to Read by Attackers Can Make Injections Less Likely

In Plain Sight II: On the Trail of Magecartwas a white paper commissioned by Arxan Technologies and produced by Aite Group. It says that its purpose is to demonstrate the massive attack surface created by electronic commerce (e-commerce) web applications that aren't being properly secured.

This lack in in-app security makes web apps vulnerable to a type of cyber attack called formjacking. Formjacking is a type of breach, where attackers inject the e-commerce checkout form with malicious code that sends buyers' credit card information to an offsite server under the hackers' control.

Eighty compromised servers were analyzed as part of this research. The companies were located in the US, Canada, Europe, Latin America and Asia.

Formjacking code is employed on the server side and executed as JavaScript in the victim's web browsers on the client side. On the web server running the e-commerce website itself is where the malicious code is inserted and renders/executes in the web browser of the victim.The credit card details are then sent from the victim's computer to the staging server owned by the attacker.

The white paper recommends some overall solutions. First is a well-documented and regularly updated vulnerability and patch management process that includes regular patching of, updates to, and penetration testing of the company's e-commerce site(s).

Second is in-app protection which implements code obfuscation and white-box cryptography to make the web forms unreadable to the adversary. This stops the adversary from injecting their field-stealing JavaScript code by making the resident code unreadable to the attacker.

Because obfuscated code can be de-obfuscated, it's also wise to adopt solutions that implement multiple layers of security, such as detection of code tampering and analysis, an active response that shuts a browser down upon detection of formjacking, and threat detection along with real-time alerting and response -- not just obfuscation.

E-commerce sites can also monitor traffic to ensure the web server is not initiating outbound connections. This should never happen under normal operating conditions, except for legitimate program updates. Deepak Patel, vice president and security evangelist with PerimeterX, commented on the situation to Security Now.

"The modern web application stack relies on third-party scripts obtained from a variety of providers, not all of whom have strong security practices," he said. "Website owners lack visibility into the third-party scripts running on the users' browsers within the context of their site. Many website owners are also unaware of all the first-party scripts running on their site. In addition to staying up to date with the latest versions of your critical platform components, website owners need to take another step: get visibility and control of all the scripts running on your website, whether first- or third-party or another part of the supply chain."

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.