Suspicious PowerShell Get-Content Piped to PowerShell (via process_creation)

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-05-25
Updated
2026-08-28

ATT&CK techniques

Execution
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Persistence

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects PowerShell reading a file with Get-Content and piping the result through Out-String into another PowerShell instance. The STEADY#URSA campaign used this pattern to execute the covert SUBTLE-PAWS backdoor stager.

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Suspicious PowerShell Get-Content Piped to PowerShell (via 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.