tldr: Swing VPN is using its user base to DDOS sites using its users as a an attack botnet.
Introduction It all started with a friend of mine complaining that his phone was doing a request to a specific app every few seconds. Initial assumption was that the phone was infected with a virus but a 2 minute investigation showed that all requests went from ‘Swing VPN’ app which were legitimately installed on the phone as VPN service.