Sigma rule: Usage Of Web Request Commands And Cmdlets - ScriptBlock

Rule

Title

Usage Of Web Request Commands And Cmdlets - ScriptBlock

Status

test

Level

medium

Author

James Pemberton / @4A616D6573

Date

2019-10-24

Modified

2025-10-20

File

rules/windows/powershell/powershell_script/posh_ps_web_request_cmd_and_cmdlets.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects the use of various web request commands with commandline tools and Windows PowerShell cmdlets (including aliases) via PowerShell scriptblock logs

Log source

product

windows

category

ps_script

definition

Requirements: Script Block Logging must be enabled

Detection

selection:
    ScriptBlockText|contains:
        - '[System.Net.WebRequest]::create'
        - 'curl '
        - 'Invoke-RestMethod'
        - 'Invoke-WebRequest'
        - ' irm ' # Space before and after to avoid false positives with 'irm' as a substring
        - 'iwr '
        # - 'Net.WebClient' # There are various other rules that cover this, so it is commented out
        - 'Resume-BitsTransfer'
        - 'Start-BitsTransfer'
        - 'wget '
        - 'WinHttp.WinHttpRequest'
filter:
    Path|startswith: 'C:\Packages\Plugins\Microsoft.GuestConfiguration.ConfigurationforWindows\'
condition: selection and not filter

False positives (as the rule lists them)

• Use of Get-Command and Get-Help modules to reference Invoke-WebRequest and Start-BitsTransfer.

Tags

• attack.execution
• attack.t1059.001

MITRE ATT&CK ids this rule names

• T1059.001

Related rules

• 9fc51a3c-81b3-4fa7-b35f-7c02cf10fd2d (derived)

References

• https://4sysops.com/archives/use-powershell-to-download-a-file-with-http-https-and-ftp/
• https://blog.jourdant.me/post/3-ways-to-download-files-with-powershell

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_web_request_cmd_and_cmdlets.yml