> It seems quite likely that this is being done via a botnet - illegally abusing thousands of people's devices. Sigh.
Just because traffic is coming from thousands of devices on residential IPs, doesn't mean it's a botnet in the classical sense. It could just as well be people signing up for a "free VPN service" — or a tool that "generates passive income" for them — where the actual cost of running the software, is that you become an exit node for both other "free VPN service" users' traffic, and the traffic of users of the VPN's sibling commercial brand. (E.g. scrapers like this one.)
This scheme is known as "proxyware" — see https://www.trendmicro.com/en_ca/research/23/b/hijacking-you...
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