Suspicious Assembly Execution via Regasm or Regsvcs From a User Path (via process_creation)

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1218.009Regsvcs/Regasm
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects regasm.exe or regsvcs.exe executing an assembly from a user, temp or ProgramData directory, a signed-binary proxy technique that runs attacker .NET code through a trusted registration utility. Regasm and Regsvcs abuse is a defense-evasion technique in the Red Canary Threat Detection Report. Detecting execution from user-writable paths surfaces trusted-binary code proxying.

Reporting behind it

Related detections7 linkedT1218.009 — drag to rearrange

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Suspicious Assembly Execution via Regasm or Regsvcs From a User Path (via process_creation)

Pivot detection · T1218.009 · 7 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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