PowerShell Download and Execute Cradle Detection

SigmaHQ Detections@sigmaHQ

•updated Oct 17, 2025•2•0•15

This rule detects common PowerShell download and execution cradles. It looks for command-line arguments that indicate an attempt to download content from the internet (e.g., '.DownloadString(', '.DownloadFile(', 'Invoke-WebRequest', 'iwr', 'Invoke-RestMethod', 'irm') combined with immediate execution (e.g., ';iex $', '| IEX', 'Invoke-Expression'). These patterns are frequently used by adversaries to fetch and execute malicious scripts or payloads directly in memory.