Adversaries may put in place resources that are referenced by a link that can be used during targeting. An adversary may rely upon a user clicking a malicious link in order to divulge information (including credentials) or to gain execution, as in Malicious Link. Links can be used for spearphishing, such as sending an email accompanied by social engineering text to coax the user to actively click or copy and paste a URL into a browser. Prior to a phish for information (as in Spearphishing Link) or a phish to gain initial access to a system (as in Spearphishing Link), an adversary must set up the resources for a link target for the spearphishing link.
Adversaries may purchase domains similar to legitimate domains (ex: homoglyphs, typosquatting, different top-level domain, etc.) during acquisition of infrastructure (Domains) to help facilitate Malicious Link. Link shortening services can also be employed. Adversaries may also use free or paid accounts on Platform-as-a-Service providers to host link targets while taking advantage of the widely trusted domains of those providers to avoid being blocked. Finally, adversaries may take advantage of the decentralized nature of the InterPlanetary File System (IPFS) to host link targets that are difficult to remove.
Silent Librarian has cloned victim organization login pages and staged them for later use in credential harvesting campaigns. Silent Librarian has also made use of a variety of URL shorteners for these staged websites.
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.
|ID||Data Source||Data Component||Detects|
|DS0035||Internet Scan||Response Content||
If infrastructure or patterns in malicious web content have been previously identified, internet scanning may uncover when an adversary has staged web content to make it accessible for targeting.Much of this activity will take place outside the visibility of the target organization, making detection of this behavior difficult. Detection efforts may be focused on other phases of the adversary lifecycle, such as during Spearphishing Link , Spearphishing Link , or Malicious Link .