Abstract: An online system transmits to a mobile device a feed story that includes a uniform resource locator (URL) of a feed story website. The online system receives from the mobile device a URL log that includes URLs that the mobile device accessed in response to requesting content from the feed story website. The online system extracts a feature of at least one URL in the log, and inputs the extracted feature into a model that was trained, using machine learning, to identify websites that perform cloaking. The model generates a score indicating a likelihood that the feed story website performs cloaking based the extracted feature. The online system compares the score to a threshold to determine whether the feed story website performs cloaking. If the online system determines that the feed story website performs cloaking, the online system limits delivery of content including the URL of the feed story website.

Abstract: A mobile device generates a first representation, based on a model, of a first content received by the mobile device from a website. An online system receives the representation of the content from the mobile device. The online system receives a second content from the website and generates a representation of the second content using the model. The online system compares the representation of the first content with the representation of the second content to determine a distance between the two representations. The distance indicates a level of similarity between the first content and the second content. The online system compares the distance between the representation of the first content and representation of the second content to determine if the distance exceeds a threshold distance. If the distance exceeds the threshold distance, the online system prevents other mobile devices from accessing the website.