Trapdoor Android Ad Fraud Scheme Hit 659 Million Daily Bid Requests Using 455 Apps
May 19, 2026
Malvertising / Mobile Security
Cybersecurity researchers have disclosed details of a new ad fraud and malvertising operation dubbed Trapdoor targeting Android device users. The activity, per HUMAN's Satori Threat Intelligence and Research Team, encompassed 455 malicious Android apps and 183 threat actor-owned command-and-control (C2) domains, turning the infrastructure into a pipeline for multi-stage fraud. "Users unwittingly download a threat actor-owned app, often a utility-style app like a PDF viewer or device cleanup tool," researchers Louisa Abel, Ryan Joye, João Marques, João Santos, and Adam Sell detailed in a report shared with The Hacker News. "These apps trigger malvertising campaigns that coerce users into downloading additional threat actor-owned apps. The secondary apps launch hidden WebViews, load threat actor-owned HTML5 domains, and request ads." The campaign, the cybersecurity company added, is self-sustaining in that an organic app install turns into an illicit re...