As articles below note this may be one of most well planned and sophisticated attacks of all time, where highly advanced malware was secretly implanted within POS register systems. The timing of attacks was also conducted at peak of e-commerce season. Impacted users should immmediately change CC# & PIN# plus carefully monitor future statements closely.
QUOTE: Not only was the digital heist huge — up to 40 million consumers might have had their data stolen — but the degree of difficulty indicates another step in the security arms race between criminals and merchants.The hack affected customers who shopped at U.S. Target retail stores between Black Friday, Nov. 27, and Dec. 15. Criminals don’t have to go through the trouble of manufacturing counterfeit credit cards, Dave Lott, retail payments risk expert at the Federal Reserve Bank of Atlanta, told NBC News. For only about $100, criminal outfits can buy equipment that allows them to print out cards for people to use at cash registers anywhere, and never be bothered for a CVV code.