Suspicious Encrypted Implant File Creation for DLL Search Order Hijacking (RainyDay Turian PlugX)

PremiumReviewedSigma · High · v1
Product
windows
Category
file_event
Author
HuntRule
Published
2026-09-10
Updated
2026-09-10

ATT&CK techniques

Execution → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects creation of encrypted implant files with distinctive names such as rdmin.src, Mcsitesdvisor.afx or winslivation.dat used by the RainyDay, Turian and PlugX variants. These files hold the encrypted payload that a legitimately signed application decrypts and loads via DLL search-order hijacking. Their appearance on disk indicates sideloading-based deployment.

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Suspicious Encrypted Implant File Creation for DLL Search Order Hijacking (RainyDay Turian PlugX)
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Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.