Detectionlowtest

PowerShell Download Via Net.WebClient - PowerShell Classic

Detects PowerShell download activity, via the .DownloadFile() or .DownloadString() methods of the Net.WebClient class. This technique is often abused by attackers to download additional payloads.

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Launch
Florian Roth (Nextron Systems)Created Sun Mar 05Updated Tue Apr 283236fcd0-b7e3-4433-b4f8-86ad61a9af2dwindows
Log Source
WindowsPowerShell Classic
ProductWindows← raw: windows
CategoryPowerShell Classic← raw: ps_classic_start
Detection Logic
Detection Logic2 selectors
detection:
    selection_webclient:
        Data|contains: 'Net.WebClient'
    selection_download:
        Data|contains:
            - '.DownloadFile('
            - '.DownloadString('
    condition: all of selection_*
False Positives

This activity may be used by legitimate software, such as patch management tools or software updaters. Investigate any such activity and apply the necessary filter.

Related Rules
Derived

65531a81-a694-4e31-ae04-f8ba5bc33759

Rule not found
Rule Metadata
Rule ID
3236fcd0-b7e3-4433-b4f8-86ad61a9af2d
Status
test
Level
low
Type
Detection
Created
Sun Mar 05
Modified
Tue Apr 28
Path
rules/windows/powershell/powershell_classic/posh_pc_download_via_webclient.yml
Raw Tags
attack.executionattack.command-and-controlattack.t1059.001attack.t1105
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