Magecart hackers used a digital credit card skimmer to steal payment card details of Newegg customers. Hackers inserted malicious Javascript code into checkout page that captured payment information of customers making purchasing on the site and then send it to a remote server. Magecart hacking group behind Ticketmaster and British Airways data breaches has now victimized popular computer hardware and consumer electronics retailer Newegg. The attack affected both desktop and mobile customers, though it is still unclear how many customers were actually hit by this credit card breach.
Source: https://thehackernews.com/2018/09/newegg-credit-card-hack.html