The Stuxnet computer worm that was used to sabotage the Iranian nuclear program was likely preceded by another sophisticated malware program. The Fanny worm is called Fanny and is part of a sophisticated malware toolset used by a cyberespionage group. Researchers from Russian antivirus firm Kaspersky Lab have dubbed Equation. Equation is considered the most advanced group of attackers to date and its activity spans back to 2001 and possibly even to 1996. Fanny is a worm that spreads through USB thumb drives and with the goal of gathering intelligence.”]
Source: https://www.csoonline.com/article/2884329/fanny-superworm-likely-the-precursor-to-stuxnet.html