Detectionhightest

Script Interpreter Execution From Suspicious Folder

Detects a suspicious script execution in temporary folders or folders accessible by environment variables

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Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)Created Tue Feb 08Updated Fri Jun 161228c958-e64e-4e71-92ad-7d429f4138bawindows

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_proc_image:
        Image|endswith:
            - '\cscript.exe'
            - '\mshta.exe'
            - '\wscript.exe'
    selection_proc_flags:
        CommandLine|contains:
            - ' -ep bypass '
            - ' -ExecutionPolicy bypass '
            - ' -w hidden '
            - '/e:javascript '
            - '/e:Jscript '
            - '/e:vbscript '
    selection_proc_original:
        OriginalFileName:
            - 'cscript.exe'
            - 'mshta.exe'
            - 'wscript.exe'
    selection_folders_1:
        CommandLine|contains:
            - ':\Perflogs\'
            - ':\Users\Public\'
            - '\AppData\Local\Temp'
            - '\AppData\Roaming\Temp'
            - '\Temporary Internet'
            - '\Windows\Temp'
    selection_folders_2:
        - CommandLine|contains|all:
              - ':\Users\'
              - '\Favorites\'
        - CommandLine|contains|all:
              - ':\Users\'
              - '\Favourites\'
        - CommandLine|contains|all:
              - ':\Users\'
              - '\Contacts\'
    condition: 1 of selection_proc_* and 1 of selection_folders_*