T1004 · threatengine.sh

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ATT&CK Technique

Winlogon Helper DLL

T1004 · persistence

▤ Generate a SIEM detection for T1004 ◈ Deployable detections for T1004 ⚠ CVEs mapped to T1004 ♛ Hunt package for T1004

Winlogon.exe is a Windows component responsible for actions at logon/logoff as well as the secure attention sequence (SAS) triggered by Ctrl-Alt-Delete. Registry entries in HKLM\Software\[Wow6432Node\]Microsoft\Windows NT\CurrentVersion\Winlogon\ and HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\ are used to manage additional helper programs and functionalities that support Winlogon. Malicious modifications to these Registry keys may cause Winlogon to load and execute malicious DLLs and/or executables.

Specifically, the following subkeys have been known to be possibly vulnerable to abuse: Winlogon\Notify - points to notification package DLLs that handle Winlogon events Winlogon\Userinit - points to userinit.exe, the user initialization program executed when a user logs on * Winlogon\Shell - points to explorer.exe, the system shell executed when a user logs on Adversaries may take advantage of these features to repeatedly execute malicious code and establish Persistence.

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 - T1004 - broken into everything you need to catch it.

The loop this page is built for (this is the job):

Understand the behaviour - read the description and the Atomic Tests to see exactly what the attacker does on a host or network.
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.
Get or write the detection - adapt ready logic (CAR Analytics, SIEM Detections, Falco, or Sigma via Generate a SIEM detection), or author your own.
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.
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 T1004, and a hunt package.

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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

MITRE ATT&CK Atomic Red Team car (MITRE)