Suspicious RegAsm Execution Spawned by Script Interpreter (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 the .NET RegAsm.exe utility launched by PowerShell, mshta, or cmd, an unusual parentage seen in ClickFix chains that used RegAsm to execute Base64-encoded XWorm. RegAsm is rarely started interactively by these interpreters in normal use.

Reporting behind it

Related detections9 linkedT1218.009 — drag to rearrange

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Malicious CloudZ RAT Persistence via schtasks Running regasm.exe

Suspicious Outbound Connection From CasPol Binary

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

Suspicious CasPol Execution Spawned by PowerShell for Injection

Suspicious PowerShell Spawning .NET LOLBIN (via process_creation)

RegAsm.exe Process Execution Missing Command-Line and Assembly Path (Windows)

Windows RegAsm.exe Initiates Network Connection to Public IP

Suspicious RegAsm Execution Spawned by Script Interpreter (via process_creation)

Pivot detection · T1218.009 · 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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