Adversaries may compromise third-party network devices that can be used during targeting. Network devices, such as small office/home office (SOHO) routers, may be compromised where the adversary's ultimate goal is not Initial Access to that environment, but rather to leverage these devices to support additional targeting. Once an adversary has control, compromised network devices can be used to launch additional operations, such as hosting payloads for Phishing campaigns (i.e., Link Target) or enabling the required access to execute Content Injection operations. Adversaries may also be able to harvest reusable credentials (i.e., Valid Accounts) from compromised network devices. Adversaries often target Internet-facing edge devices and related network appliances that specifically do not support robust host-based defenses.(Citation: Mandiant Fortinet Zero Day)(Citation: Wired Russia Cyberwar) Compromised network devices may be used to support subsequent Command and Control activity, such as Hide Infrastructure through an established Proxy and/or Botnet network.(Citation: Justice GRU 2024)
Once adversaries leverage compromised network devices as infrastructure (ex: for command and control), it may be possible to look for unique characteristics associated with adversary software, if known.(Citation: ThreatConnect Infrastructure Dec 2020) 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 related stages of the adversary lifecycle.