Adversaries may search content delivery network (CDN) data about victims that can be used during targeting. CDNs allow an organization to host content from a distributed, load balanced array of servers. CDNs may also allow organizations to customize content delivery based on the requestor’s geographical region.
Adversaries may search CDN data to gather actionable information. Threat actors can use online resources and lookup tools to harvest information about content servers within a CDN. Adversaries may also seek and target CDN misconfigurations that leak sensitive information not intended to be hosted and/or do not have the same protection mechanisms (ex: login portals) as the content hosted on the organization’s website. Information from these sources may reveal opportunities for other forms of reconnaissance (ex: Active Scanning or Search Open Websites/Domains), establishing operational resources (ex: Acquire Infrastructure or Compromise Infrastructure), and/or initial access (ex: Drive-by Compromise).
This technique cannot be easily mitigated with preventive controls since it is based on behaviors performed outside of the scope of enterprise defenses and controls. Efforts should focus on minimizing the amount and sensitivity of data available to external parties.
Much of this activity may have a very high occurrence and associated false positive rate, as well as potentially taking place outside the visibility of the target organization, making detection difficult for defenders.
Detection efforts may be focused on related stages of the adversary lifecycle, such as during Initial Access.