Detectionmediumtest

Winlogon Helper DLL

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.

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Timur Zinniatullin, oscd.communityCreated Mon Oct 21Updated Thu Jul 07851c506b-6b7c-4ce2-8802-c703009d03c0windows
Log Source
WindowsPowerShell Script
ProductWindows← raw: windows
CategoryPowerShell Script← raw: ps_script

Definition

Requirements: Script Block Logging must be enabled

Detection Logic
Detection Logic2 selectors
detection:
    selection:
        ScriptBlockText|contains: 'CurrentVersion\Winlogon'
    selection2:
        ScriptBlockText|contains:
            - 'Set-ItemProperty'
            - 'New-Item'
    condition: all of selection*
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

Rule Metadata
Rule ID
851c506b-6b7c-4ce2-8802-c703009d03c0
Status
test
Level
medium
Type
Detection
Created
Mon Oct 21
Modified
Thu Jul 07
Path
rules/windows/powershell/powershell_script/posh_ps_winlogon_helper_dll.yml
Raw Tags
attack.privilege-escalationattack.persistenceattack.t1547.004
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