Detectionhightest

LSASS Process Reconnaissance Via Findstr.EXE

Detects findstring commands that include the keyword lsass, which indicates recon actviity for the LSASS process PID

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Launch

Florian Roth (Nextron Systems)Created Fri Aug 12Updated Tue Jun 04fe63010f-8823-4864-a96b-a7b4a0f7b929windows

Log Source

WindowsProcess Creation

ProductWindows← raw: windows

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection_findstr_img:
        - Image|endswith:
              - '\find.exe'
              - '\findstr.exe'
        - OriginalFileName:
              - 'FIND.EXE'
              - 'FINDSTR.EXE'
    selection_findstr_cli:
        CommandLine|contains: 'lsass'
    selection_special:
        CommandLine|contains|windash:
            - ' /i "lsass'
            - ' /i lsass.exe'
            - 'findstr "lsass'
            - 'findstr lsass'
            - 'findstr.exe "lsass'
            - 'findstr.exe lsass'
    condition: all of selection_findstr_* or selection_special