Suspicious DotNet Utility Spawned by Script Host for Hollowing (via process_creation)

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-08-25
Updated
2026-08-28

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 RegAsm, MSBuild, or AddInProcess32 launched by a script host or mshta. This layered loader spawns these signed .NET utilities as process hollowing targets for its final payload.

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Possible Process Injection Target RegAsm Launched Without Arguments via Process Creation
In-Memory Regasm Process Hollowing Spawned by PowerShell (via process_creation)
Suspicious AppLaunch.exe Execution as Process Hollowing Target
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Suspicious DotNet Utility Spawned by Script Host for Hollowing (via process_creation)
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.