Event Triggered Execution: Windows Management Instrumentation Event Subscription
Other sub-techniques of Event Triggered Execution (15)
|T1546.001||Change Default File Association|
|T1546.003||Windows Management Instrumentation Event Subscription|
|T1546.004||.bash_profile and .bashrc|
|T1546.007||Netsh Helper DLL|
|T1546.012||Image File Execution Options Injection|
|T1546.015||Component Object Model Hijacking|
Adversaries may establish persistence and elevate privileges by executing malicious content triggered by a Windows Management Instrumentation (WMI) event subscription. WMI can be used to install event filters, providers, consumers, and bindings that execute code when a defined event occurs. Examples of events that may be subscribed to are the wall clock time, user loging, or the computer's uptime. 
Adversaries may use the capabilities of WMI to subscribe to an event and execute arbitrary code when that event occurs, providing persistence on a system.   Adversaries may also compile WMI scripts into Windows Management Object (MOF) files (.mof extension) that can be used to create a malicious subscription.  
WMI subscription execution is proxied by the WMI Provider Host process (WmiPrvSe.exe) and thus may result in elevated SYSTEM privileges.
|Privileged Account Management||
Prevent credential overlap across systems of administrator and privileged accounts. 
|User Account Management||
By default, only administrators are allowed to connect remotely using WMI; restrict other users that are allowed to connect, or disallow all users from connecting remotely to WMI.
Monitor WMI event subscription entries, comparing current WMI event subscriptions to known good subscriptions for each host. Tools such as Sysinternals Autoruns may also be used to detect WMI changes that could be attempts at persistence.  
Monitor processes and command-line arguments that can be used to register WMI persistence, such as the
Register-WmiEvent PowerShell cmdlet , as well as those that result from the execution of subscriptions (i.e. spawning from the WmiPrvSe.exe WMI Provider Host process).
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