Detectionhightest

LSASS Access Detected via Attack Surface Reduction

Detects Access to LSASS Process

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Markus NeisCreated Sun Aug 26Updated Sat Aug 13a0a278fe-2c0e-4de2-ac3c-c68b08a9ba98windows

Log Source

Windowswindefend

ProductWindows← raw: windows

Servicewindefend← raw: windefend

Definition

Requirements:Enabled Block credential stealing from the Windows local security authority subsystem (lsass.exe) from Attack Surface Reduction (GUID: 9e6c4e1f-7d60-472f-ba1a-a39ef669e4b2)

Detection Logic

detection:
    selection:
        EventID: 1121
        Path|endswith: '\lsass.exe'
    filter_thor:
        ProcessName|startswith: 'C:\Windows\Temp\asgard2-agent\'
        ProcessName|endswith:
            - '\thor64.exe'
            - '\thor.exe'
    filter_exact:
        ProcessName:
            - 'C:\Windows\System32\atiesrxx.exe'
            - 'C:\Windows\System32\CompatTelRunner.exe'
            - 'C:\Windows\System32\msiexec.exe'
            - 'C:\Windows\System32\nvwmi64.exe'
            - 'C:\Windows\System32\svchost.exe'
            - 'C:\Windows\System32\Taskmgr.exe'
            - 'C:\Windows\System32\wbem\WmiPrvSE.exe'
            - 'C:\Windows\SysWOW64\msiexec.exe'
    filter_begins:
        ProcessName|startswith:
            - 'C:\Windows\System32\DriverStore\'
            - 'C:\WINDOWS\Installer\'
            - 'C:\Program Files\'
            - 'C:\Program Files (x86)\'
    condition: selection and not 1 of filter_*