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AppInit DLLs - T1546.010 (cc89ecbd-3d33-4a41-bcca-001e702d18fd)

Adversaries may establish persistence and/or elevate privileges by executing malicious content triggered by AppInit DLLs loaded into processes. Dynamic-link libraries (DLLs) that are specified in the AppInit_DLLs value in the Registry keys HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Windows or HKEY_LOCAL_MACHINE\Software\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Windows are loaded by user32.dll into every process that loads user32.dll. In practice this is nearly every program, since user32.dll is a very common library. (Citation: Elastic Process Injection July 2017)

Similar to Process Injection, these values can be abused to obtain elevated privileges by causing a malicious DLL to be loaded and run in the context of separate processes on the computer. (Citation: AppInit Registry) Malicious AppInit DLLs may also provide persistence by continuously being triggered by API activity.

The AppInit DLL functionality is disabled in Windows 8 and later versions when secure boot is enabled. (Citation: AppInit Secure Boot)

Cluster A Galaxy A Cluster B Galaxy B Level
AppInit DLLs - T1546.010 (cc89ecbd-3d33-4a41-bcca-001e702d18fd) Attack Pattern Event Triggered Execution - T1546 (b6301b64-ef57-4cce-bb0b-77026f14a8db) Attack Pattern 1