US Patent 9374385 Remediating computer security threats using distributed sensor computers

A data processing system comprises a security control computer performing operations comprising: receiving, an advertising exchange network computer, advertising presentation data indicating presentations of advertisements to particular browsers that have browsed to particular websites; determining, based upon detection data, whether the particular websites are associated with network attacks or malware; in response, storing transit data specifying computers that have visited the particular web sites and using the transit data to determine a plurality of particular web pages to inspect for threats; based on a hierarchical structure of the particular web pages and without consideration of content of the particular web pages, identifying one or more features, of links in the particular web page or files referenced in the particular web pages, that indicate one or more security threats in the web pages; and determining remediation measures to remediate security threats that are identified in one of the particular web pages.