huntrule

Windows Process Creation: OfflineScannerShell.exe mpclient.dll DLL Sideloading Risk

Detects OfflineScannerShell.exe launched with an unexpected current directory that could enable mpclient.dll sideloading.

FreeReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
frack113 (SigmaHQ), DRL 1.1
Published
2022-03-06
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

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 executions of OfflineScannerShell.exe where the process is launched from a non-standard current directory, indicating possible DLL sideloading behavior. OfflineScannerShell.exe is sensitive to loading a DLL named mpclient.dll from the working directory, so attackers can exploit this to run malicious code. The detection relies on process creation telemetry fields including the image path and the process current directory to identify deviations from the expected Offline directory.

Reporting behind it

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Windows Process Creation: OfflineScannerShell.exe mpclient.dll DLL Sideloading Risk
Pivot detection · T1218 · 9 related

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