huntrule

Windows PowerShell Download and Execution Cradles

Flags PowerShell commands that download remote content and immediately execute it using IEX/Invoke-Expression.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-03-24
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

Execution

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule identifies PowerShell command lines that combine common download functions (such as DownloadString, DownloadFile, Invoke-WebRequest, and Invoke-RestMethod) with execution via Invoke-Expression/IEX. This pattern is a common attacker technique to fetch remote content and immediately execute it in the same PowerShell context. The detection relies on Windows process creation telemetry, specifically the full CommandLine field for PowerShell processes.

Reporting behind it

Related detections9 linkedT1059 — drag to rearrange
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Malicious AutoHotKey Runner AutoNotify Executing AHKBot Looper Script (via process_creation)
Malicious IIS Worker Process Spawning Command Shell after ASP.NET ViewState Injection (via process_creation)
Suspicious MSSQL xp_cmdshell Enablement via sp_configure (via process_creation)
Windows PowerShell Download and Execution Cradles
Pivot detection · T1059 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.