Major hacks at retailers that include Target and Neiman Marcus have put a new spotlight on the security of point-of-sale (POS) systems. What may come as a surprise to some is that the memory-scraping malware attacks were nothing new. Last year, Visa published two "Visa Data Security Alerts" warning merchants of an increase in attacks targeting credit card data with specific references to memory-scraping malware.
http://www.darkreading.com/attacks-breaches/tech-insight-defending-point-of-sale-sys/240165629