  Social media trolling is a powerful tactic to manipulate public opinion on
issues with a high moral component. Troll farms, as evidenced in the past,
created fabricated content to provoke or silence people to share their opinion
on social media during the US presidential election in 2016. In this paper, we
introduce an alternate way of provoking or silencing social media discourse by
manipulating how users perceive authentic content. This manipulation is
performed by man-in-the-middle malware that covertly rearranges the linguistic
content of an authentic social media post and comments. We call this attack
Malware-Induced Misperception (MIM) because the goal is to socially engineer
spiral-of-silence conditions on social media by inducing perception. We
conducted experimental tests in controlled settings (N = 311) where a malware
covertly altered selected words in a Facebook post about the freedom of
political expression on college campuses. The empirical results (1) confirm the
previous findings about the presence of the spiral-of-silence effect on social
media; and (2) demonstrate that inducing misperception is an effective tactic
to silence or provoke targeted users on Facebook to express their opinion on a
polarizing political issue.
