In 2009, one or more prestigious researchers received a CD by mail that contained pictures and other materials from a recent scientific conference they attended in Houston. The scientists didn't know it then, but the disc also delivered a malicious payload developed by a highly advanced hacking operation that had been active since at least 2001. The CD, it seems, was tampered with on its way through the mail. (...)
Taken together, the accomplishments led Kaspersky researchers to conclude that Equation Group is probably the most sophisticated computer attack group in the world, with technical skill and resources that rival the groups that developed Stuxnet and the Flame espionage malware.
relatório das Kaspersky (pdf)