- Tactics
- Privilege Escalation , Persistence
- Platforms
- Windows
- Reference
- attack.mitre.org/techniques/T1546.010
Description
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)
How GTK Cyber trains on this
GTK Cyber's Threat Hunting with Data Science course teaches you to build machine-learning detections for techniques like this across the MITRE ATT&CK framework, including the Privilege Escalation, Persistence tactic this technique falls under. Practitioner-led, focused on real detections, not memorizing technique IDs.
Related techniques
- T1037 — Boot or Logon Initialization Scripts
- T1053 — Scheduled Task/Job
- T1055 — Process Injection
- T1068 — Exploitation for Privilege Escalation
- T1078 — Valid Accounts
- T1098 — Account Manipulation
- T1112 — Modify Registry
- T1133 — External Remote Services
- T1134 — Access Token Manipulation
- T1136 — Create Account
- T1137 — Office Application Startup
- T1176 — Software Extensions