Cybersecurity researchers have uncovered a massive ad fraud operation known as “Scallywag,” which exploits WordPress plugins to generate over 1.4 billion fraudulent ad requests daily. This operation targets pirated content sites, using complex redirection techniques and intermediary pages to serve ads in a hidden manner. Instead of placing ads directly on piracy sites, Scallywag inserts deceptive intermediary pages filled with ads and links, camouflaging the true nature of the operation. These intermediary pages are designed to look harmless when directly accessed, but they redirect users to illicit content when accessed via piracy catalogs.
Scallywag operates as a “fraud-as-a-service” model, offering WordPress plugins to a global network of aspiring cybercriminals. The plugin enables users to set up their own ad fraud schemes, which are often shared through instructional videos available on platforms like YouTube. This model has created a community of digital pirates, with various independent actors utilizing the same techniques to generate revenue. By distributing the tools, Scallywag allows others to easily set up their own fraudulent operations, maximizing ad revenue for both plugin creators and customers.
A significant feature of Scallywag is its use of open redirectors to mask referral sources, which makes it harder for advertisers to identify fraudulent traffic.
The redirectors make it appear as though traffic originates from legitimate sources, such as search engines or social networks, rather than piracy sites. This tactic has made the operation harder to detect and has allowed it to persist under the radar. At its peak in early 2024, Scallywag was generating 1.4 billion fraudulent ad requests per day, leading to significant financial harm in the advertising ecosystem.
After the scheme was uncovered by HUMAN’s Satori Threat Intelligence and Research Team, the impact of Scallywag has decreased by 95%. HUMAN’s Defense Platform now actively detects and blocks traffic related to the operation, significantly reducing its reach. However, Scallywag’s operators continue to evolve, frequently rotating domains and adapting their tactics to evade detection.
