1. A method comprising: receiving a uniform resource locator (URL) that includes one or more substrings, wherein each substring comprises a plurality of alphanumeric characters; extracting, via one or more processors, a plurality of features associated with the URL; determining, as at least one of the plurality of features, a similarity measure between a whole or part of the URL and a brand name associated with an authentic resource or a legitimate entity; and applying one or more classification models to the one or more features to determine whether a resource located by the URL is an unauthentic resource.