Cloak and Dagger: Dynamics of Web Search Cloaking
Cloaking is a common "Bait-and-switch" technique used to hide the true nature of a Web site by delivering blatantly different semantic content to different user segments. It is often used in Search Engine Optimization (SEO) to obtain user traffic illegitimately for scams. In this paper, the authors measure and characterize the prevalence of cloaking on different search engines, how this behavior changes for targeted versus untargeted advertising and ultimately the response to site cloaking by search engine providers. Using a custom crawler, called Dagger, they track both popular search terms (e.g., as identified by Google, Alexa and Twitter) and targeted keywords (focused on pharmaceutical products) for over five months, identifying when distinct results were provided to crawlers and browsers.