Techniques › T1547.010 › AN0580
AN0580 Analytic 0580
Windows · attack.mitre.org · ATT&CK Enterprise v19.2
<p>Detects suspicious registry modifications under
HKLM\SYSTEM\CurrentControlSet\Control\Print\Monitors\*\Driver, DLL loads by spoolsv.exe of non-standard or unsigned modules, and abnormal usage of the AddMonitor API by non-installation processes. This pattern often indicates an attempt to persist a malicious DLL via the print monitor mechanism, particularly when correlated with creation of files in C:\Windows\System32 not tied to known patches or installations.</p>- Detects
- T1547.010 Port Monitors
- Part of
- DET0204 Detection Strategy for T1547.010 – Port Monitor DLL Persistence via spoolsv.exe (Windows)
Log sources and channels
Exactly as MITRE states them in x_mitre_log_source_references. Where a channel is vague, it is vague in the source; kevmap does not tidy it.
| Log source | Channel | Data component |
|---|---|---|
| WinEventLog:Sysmon | EventCode=1 | DC0032 Process Creation |
| WinEventLog:Sysmon | EventCode=7 | DC0016 Module Load |
| WinEventLog:Sysmon | EventCode=13 | DC0063 Windows Registry Key Modification |
| WinEventLog:Sysmon | EventCode=11 | DC0039 File Creation |
| WinEventLog:Application | API call to AddMonitor invoked by non-installer process | DC0021 OS API Execution |
Mutable elements
Parameters MITRE marks as environment-specific. These are the knobs you are expected to tune; they are why an analytic is not a rule.
| Field | Description |
|---|---|
TargetDLLDirectory | Expected directory path for legitimate monitor DLLs (e.g., C:\Windows\System32) |
SignedImageValidation | Enable/disable signature validation on DLLs loaded by spoolsv.exe |
UserContextScope | Define whether only SYSTEM/user installs are expected to make changes to the port monitor registry keys |
TimeWindow | Timeframe between registry modification and subsequent spoolsv.exe DLL load |
AddMonitorCallContext | Filter on calling process of AddMonitor API to detect anomalies outside installer/updater |