A hacking group known as "Keeper" is responsible for security breaches at more than 570 online e-commerce portals over the last three years.
The Keeper gang broke into online store backends, altered their source code, and inserted malicious scripts that logged payment card details entered by shoppers in checkout forms.
These types of attacks are what the cyber-security community calls web skimming, e-skimming, or "Magecart" intrusions (named so after the first hacker group that used these tactics).
Keeper gang has been active since April 2017
In a report published today by threat intelligence firm Gemini Advisory, the company says that Keeper has been operating since at least April 2017, and continues to operate even today. more here