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

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-20
Updated
2026-09-20

ATT&CK techniques

Priv Esc → Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Cred Access

  7. Discovery

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule detects RegSvcs.exe or aspnet_compiler.exe launched by a scripting host such as wscript, cscript or PowerShell, an unusual parent-child pair the ProjFUD injector uses as a hollowing target for AsyncRAT. These .NET utilities have no reason to be started by script interpreters. Detecting the chain reveals code injection into a trusted signed binary.

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Suspicious .NET Utility Spawned by AutoHotkey Loader for Process Hollowing (via process_creation)
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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.