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ATT&CK Technique

Port Monitors

T1013 · persistence, privilege-escalation
▤ Generate a SIEM detection for T1013 ◈ Deployable detections for T1013 ⚠ CVEs mapped to T1013 ♛ Hunt package for T1013

A port monitor can be set through the API call to set a DLL to be loaded at startup. This DLL can be located in C:\Windows\System32 and will be loaded by the print spooler service, spoolsv.exe, on boot. The spoolsv.exe process also runs under SYSTEM level permissions.

Alternatively, an arbitrary DLL can be loaded if permissions allow writing a fully-qualified pathname for that DLL to HKLM\SYSTEM\CurrentControlSet\Control\Print\Monitors. The Registry key contains entries for the following: Local Port Standard TCP/IP Port USB Monitor WSD Port Adversaries can use this technique to load malicious code at startup that will persist on system reboot and execute as SYSTEM.

Windows
How to use this page - the detection-engineering loop
Attackers have goals (tactics - “get credentials”, “move laterally”) and techniques are the concrete methods they use to reach them. This page is one method - T1013 - broken into everything you need to catch it.
The loop this page is built for (this is the job):
  1. Understand the behaviour - read the description and the Atomic Tests to see exactly what the attacker does on a host or network.
  2. Find the telemetry - what data source would reveal it (process creation, registry, network flow, auth logs). Detection Coverage shows which surfaces already have a rule and which are blind.
  3. Get or write the detection - adapt ready logic (CAR Analytics, SIEM Detections, Falco, or Sigma via Generate a SIEM detection), or author your own.
  4. Test it - run an Atomic Test in a lab and confirm your rule actually fires. A detection you have not tested is a hope, not coverage.
  5. Deploy and tune - push it, then watch for false positives and adjust.
What each panel is for:
Atomic Testssafely reproduce the technique in a lab to validate that a detection fires. Detection Coveragewhich detection surfaces have a rule for this technique; none is a blind spot to close, or simply not applicable (YARA matches files, not network behaviour). CAR / SIEM / Falcoready-made detection logic (Splunk SPL, Elastic EQL, Sentinel KQL, Falco) you adapt to your own SIEM. Mitigationsreduce exposure so the technique is harder to use at all - prevent, not just detect. Actors / Attributionwho actually uses this, so you prioritise by your own threat model. Attack Path / LOTLwhat attackers do before and after this step, and the legitimate tools they abuse to do it.
Where this fits: you usually arrive here from a CVE (“which techniques does it enable”) and leave with a tested detection deployed. The buttons above jump straight to building one, the deployable rules, the CVEs that use T1013, and a hunt package.

Detection Coverage

0/9 layers
Coverage across standard detection surfaces. Rows marked none have no rule of that type mapped. Some are real blind spots worth closing; others are simply not applicable to this technique (e.g. YARA matches malware files, not network behaviour).
Behavioral / log (Sigma) none
Analytics (MITRE CAR) none
Runtime / container (Falco) none
File / malware (YARA) none
Network (Suricata/Snort) none
Vuln scan (Nuclei) none
SIEM (Splunk ESCU) none
SIEM (Elastic) none
SIEM (Azure Sentinel) none
External lookups - second-class, for what we don’t hold ourselves