Malicious Office Application Loading a User-Path DLL via Regsvr32 or Rundll32 (via process_creation)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1204.002Malicious File
Persistence
Priv Esc
Defense Evasion
- T1218.010Regsvr32
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a Microsoft Office application spawning regsvr32 or rundll32 to load a DLL from a user-writable path such as AppData, Temp or ProgramData, the macro-driven loader pattern used by families like Emotet to execute their payload after a malicious document is opened. This document-to-DLL execution chain is documented in the Red Canary Threat Detection Report. Detecting the Office-to-DLL proxy execution surfaces the intrusion at the initial-access boundary.

Reporting behind it

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Malicious Office Application Loading a User-Path DLL via Regsvr32 or Rundll32 (via process_creation)

Pivot detection · T1204.002 · 9 related

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

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