We used to call residential proxies (software that runs unexpectedly on a random person's device and relays someone else's internet traffic to hide its origin or get around network-based restrictions) "malware," and an application which appeared to be legit but did something like this behind the scenes was called a "Trojan horse"...until someone realized they could bury it in an app's terms of service and do it "legally."

https://mastodon.social/@senslayer/117462401396318225