DOUBLEFANTASY is a POSIX-compliant, multiplatform malware written by the Equation Group.
https://toddcullumresearch.com/2017/04/13/equationgroup-doublefantasy-part-1/
https://malpedia.caad.fkie.fraunhofer.de/details/win.doublefantasy
https://twitter.com/Int2e_/status/1294565186939092994
https://securelist.com/equation-the-death-star-of-malware-galaxy/68750/
DEAD LINK https://fmnagisa.wordpress.com/2020/08/27/revisiting-equationgroups-fanny-worm-or-dementiawheel/