Kaspersky originally spotted Careto in a spear phishing email campaign, where this campaign hopes to entice the recipient over to malicious websites that have been disguised as news sites such as The Guardian and the Washington Post. As for the authors, they do seem to be native in the Spanish language.
This particular campaign was active for at least five years until January this year, since some Careto samples were compiled in 2007. Throughout the entire effort put in by Kaspersky Lab’s investigations, the command-and-control (C&C) servers were actually shut down. Infections have happened in Algeria, Argentina, Belgium, Bolivia, Brazil, China, Colombia, Costa Rica, Cuba, Egypt, France, Germany, Gibraltar, Guatemala, Iran, Iraq, Libya, Malaysia, Mexico, Morocco, Norway, Pakistan, Poland, South Africa, Spain, Switzerland, Tunisia, Turkey, United Kingdom, United States and Venezuela. While there are different attack vectors used, one of them would be the Adobe Flash Player exploit (CVE-2012-0773). [Press Release]