huntrule

Windows PowerShell Script Block Matches Common Reflection and Injection Keywords

Alerts on PowerShell script block text containing reflection, dynamic assembly loading, and injection-related keywords.

FreeReviewedSigma · Medium · v2
Product
windows
Category
ps_script
Author
Florian Roth (Nextron Systems), Perez Diego (@darkquassar), Tuan Le (NCSGroup) (SigmaHQ), DRL 1.1
Published
2019-02-11
Updated
2026-07-31
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 PowerShell script block content containing specific .NET reflection, assembly loading, interop, and injection-related keywords often seen in exploitation frameworks. Attackers may use these constructs to load assemblies dynamically, resolve unmanaged functions, or perform execution and process manipulation within PowerShell. It relies on telemetry that captures PowerShell script block text, such as Script Block Logging, and matches on substring presence for the listed patterns.

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
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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 Script Block Matches Common Reflection and Injection Keywords
Pivot detection · T1059.001 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

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