huntrule

Windows mpclient.dll Sideloading via MpCmdRun.exe or NisSrv.exe from Non-Default Paths

Alerts when mpclient.dll is loaded by MpCmdRun.exe or NisSrv.exe outside known Windows Defender directories.

FreeReviewedSigma · High · v2
Product
windows
Category
image_load
Author
Bhabesh Raj (SigmaHQ), DRL 1.1
Published
2022-08-02
Updated
2026-07-31
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 flags image loads of mpclient.dll when performed by Windows Defender-related processes MpCmdRun.exe and NisSrv.exe from directories outside common, expected locations. Sideloading a DLL from an atypical path can allow an attacker to run malicious code under the context of a trusted binary, supporting persistence and stealth. It relies on Windows image load telemetry capturing the loaded DLL path and the importing process image path.

Reporting behind it

Related detections9 linkedT1574.001 — drag to rearrange
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Suspicious wmicodegen.dll Sideload by inetinfo.exe (UAT-8099 Cobalt Strike)
Suspicious LucidRook DismCore.dll Side-Load into Browser Process
Suspicious Encrypted Implant File Creation for DLL Search Order Hijacking (RainyDay Turian PlugX)
Suspicious RoboForm Signed Binary Executed From Non-Standard Path (via process_creation)
Malicious dal_keepalives.dll Sideloaded By Signed Binary (via image_load)
Suspicious Cortex XDR Binary Sideloading winutils.dll (via image_load)
Windows mpclient.dll Sideloading via MpCmdRun.exe or NisSrv.exe from Non-Default Paths
Pivot detection · T1574.001 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.