1. A computer-implemented method, comprising: identifying two or more web pages, wherein each web page is associated with one or more features and with a respective score indicating whether the web page contains inappropriate or malicious content, and each feature from the one or more features is associated with a respective score indicating whether the feature is associated with inappropriate or malicious content, wherein at least one feature from the one or more features is a common feature between two or more of the identified web pages; generating a graph linking each of the identified web pages with the one or more features associated with each web page; performing a random walk on the graph, wherein: (i) the respective score of each web page reached in the random walk is updated based on a function of the current score of the web page and the respective score of the features linked to the web page in the graph, wherein the respective scores of the features linked to the web page are propagated to the web page along edges of the graph, and (ii) the respective score of each feature reached in the random walk is updated based on a function of the current score of the feature and the respective scores of the one or more web pages linked to the feature in the graph, wherein the respective scores of the one or more web pages linked to the feature are propagated to the feature along edges of the graph; for each web page, determining whether the respective updated score meets a threshold; and identifying the web page associated with the updated score that meets the threshold as a web page that an advertiser associated with the respective web page can use as a landing page for an advertisement.