huntrule

Windows PowerShell execution with download-related command line patterns

Alerts when PowerShell is started with command-line fragments indicative of downloading remote content.

FreeReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
Florian Roth (Nextron Systems), oscd.community, Jonhnathan Ribeiro (SigmaHQ), DRL 1.1
Published
2019-01-16
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 flags process creation events where PowerShell (powershell.exe, powershell_ise.exe, or pwsh.exe) is launched and its command line contains specific download-related constructs. Attackers often use PowerShell to fetch remote content or stage payloads, and the presence of these string fragments indicates automated download behavior. The detection relies on Windows process creation telemetry, matching the process image and command line substrings.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange
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Malicious Script Host Spawning PowerShell in Gootloader Chain
Suspicious PsExec Service Launching Encoded PowerShell Payload
Suspicious PowerShell Remote Script Execution via IEX DownloadString
Malicious SharePoint ToolShell Post-Exploitation via Encoded PowerShell (via process_creation)
Suspicious In-Memory PowerShell Execution from Web Server via Automation Assembly (via image_load)
Malicious Qilin Chrome Credential Harvesting Script Execution via IPScanner (via process_creation)
Windows PowerShell execution with download-related command line patterns
Pivot detection · T1059.001 · 9 related

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