PowerShell ExportedCommands Array Index for Indirect Cmdlet Execution (Windows Process Creation)

Flags PowerShell command lines that enumerate Microsoft.PowerShell.Utility exported commands and invoke them via array index.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Norbert Jaśniewicz (AlphaSOC), Swachchhanda Shrawan Poudel (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2026-10-06
Updated
2026-10-07

ATT&CK techniques

Execution → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Persistence

  5. Priv Esc

  6. Cred Access

  7. Discovery

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule identifies PowerShell command lines that enumerate Microsoft.PowerShell.Utility exported commands via ExportedCommands.Values and then invoke cmdlets indirectly using array index access. Attackers can use this technique to reduce reliance on explicit strings associated with common cmdlets, making simple command-line matching less effective. It relies on Windows process creation telemetry that includes the PowerShell image name and the full command line content.

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PowerShell ExportedCommands Array Index for Indirect Cmdlet Execution (Windows Process Creation)
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.