Adversaries may use port monitors to run an adversary supplied DLL during system boot for persistence or privilege escalation. A port monitor can be set through the AddMonitor API call to set a DLL to be loaded at startup.[1] This DLL can be located in C:\Windows\System32 and will be loaded and run by the print spooler service, spoolsv.exe, under SYSTEM level permissions on boot.[2]
Alternatively, an arbitrary DLL can be loaded if permissions allow writing a fully-qualified pathname for that DLL to the Driver value of an existing or new arbitrarily named subkey of HKLM\SYSTEM\CurrentControlSet\Control\Print\Monitors. The Registry key contains entries for the following:
- Local Port
- Standard TCP/IP Port
- USB Monitor
- WSD Port
References
- Microsoft. (n.d.). AddMonitor function. Retrieved September 12, 2024.
- Bloxham, B. (n.d.). Getting Windows to Play with Itself [PowerPoint slides]. Retrieved November 12, 2014.
Kwistjonijiet marbuta
| Tip ta’ link | Kwistjoni |
|---|---|
| is related to | Techniques |
| is blocked by | Detection Strategy for T1547.010 – Port Monitor DLL Persistence via spoolsv.exe (Windows) |
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