huntrule

Windows PowerShell Base64 Encoded Commands Containing Invoke- ( -e )

Flags PowerShell executions using the -e encoded command flag with Base64 patterns consistent with an Invoke- call.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
pH-T (Nextron Systems), Harjot Singh, @cyb3rjy0t (SigmaHQ), DRL 1.1
Published
2022-05-20
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 identifies process executions of PowerShell (powershell.exe or pwsh.exe) where the command line includes the encoded command flag (-e) and the encoded payload matches Base64 fragments consistent with an 'Invoke-' call. Attackers frequently use Base64-encoded PowerShell to obscure script content and reduce casual inspection. The detection relies on process creation telemetry including the executable path and the raw command-line string.

Reporting behind it

Related detections9 linkedT1027 — drag to rearrange
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Suspicious PowerShell AES Decryption and Reflective Method Invocation in SolarMarker
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Windows PowerShell Base64 Encoded Commands Containing Invoke- ( -e )
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.