huntrule

PowerShell command-line obfuscation indicators from special-character patterns (Windows)

Alerts on PowerShell executions whose command lines contain repeated special-character obfuscation patterns.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Teymur Kheirkhabarov (idea), Vasiliy Burov (rule), oscd.community, Tim Shelton (fp) (SigmaHQ), DRL 1.1
Published
2020-10-15
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

Execution → Defense Evasion

  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 Windows process creations where the executed binary is PowerShell (powershell.exe/pwsh.exe) and the command line contains repeated special-character patterns consistent with obfuscation. Attackers often use such formatting to hinder parsing and analysis while still running the same scripts. It relies on process creation telemetry, matching the command line against multiple regular-expression indicators and using image/path and optional allowlists to reduce known benign activity.

Reporting behind it

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Obfuscated Encoded PowerShell Payload Deployed - PowerShell (via powershell)
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PowerShell command-line obfuscation indicators from special-character patterns (Windows)
Pivot detection · T1027 · 9 related

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