huntrule

Suspicious PowerShell Decoding Base64 Payload Stored in Registry

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-10-10
Updated
2026-10-10
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 detects PowerShell reading a value from the HKLM SOFTWARE\System key and base64 decoding it in memory. The ClipBanker loader stored a base64 PowerShell stage inside a registry Config value and used a scheduled task to decode and run it as documented by Kaspersky. Fileless retrieval of an encoded payload from the registry is a hallmark of staged, evasive execution.

Reporting behind it

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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.