Detectionhightest

Suspicious Invoke-WebRequest Execution

Detects a suspicious call to Invoke-WebRequest cmdlet where the and output is located in a suspicious location

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Nasreddine Bencherchali (Nextron Systems)Created Tue Aug 02Updated Fri Jul 185e3cc4d8-3e68-43db-8656-eaaeefdec9ccwindows

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_img:
        - Image|endswith:
              - '\powershell_ise.exe'
              - '\powershell.exe'
              - '\pwsh.exe'
        - OriginalFileName:
              - 'powershell_ise.EXE'
              - 'PowerShell.EXE'
              - 'pwsh.dll'
    selection_commands:
        CommandLine|contains:
            # These are all aliases of Invoke-WebRequest
            - 'curl '
            - 'Invoke-WebRequest'
            - 'iwr '
            - 'wget '
    selection_flags:
        CommandLine|contains:
            - ' -ur'
            - ' -o'
    selection_susp_locations:
        CommandLine|contains:
            - '\AppData\'
            - '\Desktop\'
            - '\Temp\'
            - '\Users\Public\'
            - '%AppData%'
            - '%Public%'
            - '%Temp%'
            - '%tmp%'
            - ':\Windows\'
    condition: all of selection_*