We recently came across a simple Magento credit card skimmer found on a compromised website that was loading from the malicious domain magecart[.]net.
The malicious domain was first registered on December 8th, 2019 and is likely a blatant play on the hacker groups known under the collective name MageCart. This renowned group of threat actors regularly targets online shopping carts to steal payment and personal information.
We located the malicious file at ./pub/static/frontend/Infortis/ultimo/en_US/Magento_Checkout/template/billing-address.html on the compromised Magento website.
The skimmer loads an iframe from a single line from HTML file onto the checkout page of a compromised Magento website, offering users a legitimate-looking area to input payment purchase information.
A form field is then used to collect the payment card details and personal information of the victim.
Once all fields have been populated with data, a click event from the form submission triggers the function pay_save to exfiltrate the unencrypted stolen information back to the malicious domain magecart[.]net.
Data exfiltration is performed using JavaScript to capture the input from the form’s interface, then collects and condenses the information to the result variable so that it can finally be sent to a PHP script on the malicious magecart[.]net domain.