System Shutdown/Reboot

Tactics: impact

Adversaries may shutdown/reboot systems to interrupt access to, or aid in the destruction of, those systems. Operating systems may contain commands to initiate a shutdown/reboot of a machine or network device. In some cases, these commands may also be used to initiate a shutdown/reboot of a remote computer or network device via Network Device CLI (e.g. <code>reload</code>). They may also include shutdown/reboot of a virtual machine via hypervisor / cloud consoles or command line tools. Shutting down or rebooting systems may disrupt access to computer resources for legitimate users while also impeding incident response/recovery. Adversaries may also use Windows API functions, such as InitializeSystemShutdownExW or ExitWindowsEx, to force a system to shut down or reboot. Alternatively, the NtRaiseHardErroror ZwRaiseHardError Windows API functions with the ResponseOption parameter set to OptionShutdownSystem may deliver a “blue screen of death” (BSOD) to a system. In order to leverage these API functions, an adversary may need to acquire SeShutdownPrivilege (e.g., via Access Token Manipulation). In some cases, the system may not be able to boot again. Adversaries may attempt to shutdown/reboot a system after impacting it in other ways, such as Disk Structure Wipe or Inhibit System Recovery, to hasten the intended effects on system availability.