Suspicious RegAsm Spawned as Process Hollowing Target

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1055.012Process Hollowing
Defense Evasion
- T1055.012Process Hollowing
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects RegAsm.exe launched as a child of script hosts such as wscript, cscript or powershell, a process hollowing target abused by SwaetRAT and Ande Loader to run injected code under a signed .NET utility. RegAsm normally runs during development, so execution from a scripting parent indicates injection rather than legitimate assembly registration.

Reporting behind it

Related detections9 linkedT1055.012 — drag to rearrange

Suspicious SearchIndexer Process Started by Non-Service Parent for Hollowing

Suspicious Browser Updater Binary Spawned by AutoIt for Process Hollowing

Suspicious DotNet Utility Spawned by Script Host for Process Hollowing via Command Line

Suspicious Outbound Network Connection from msiexec.exe (via network_connection)

Suspicious Outbound Connection from tracerpt.exe after Process Hollowing (via network_connection)

Suspicious AddInProcess32 Outbound Connection after Process Hollowing

Suspicious microsoftedgeupdatecore Outbound Connection from Wrong Path

Suspicious RegAsm or AppLaunch Outbound Connection after Injection

Suspicious DotNet Utility MSBuild RegAsm RegSvcs Network Beacon Indicating Hollowing

Suspicious RegAsm Spawned as Process Hollowing Target

Pivot detection · T1055.012 · 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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