Microsoft Build Engine Started an Unusual Processedit

An instance of MSBuild, the Microsoft Build Engine, started a PowerShell script or the Visual C# Command Line Compiler. This technique is sometimes used to deploy a malicious payload using the Build Engine.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-windows.*

Severity: low

Risk score: 21

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100



  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Defense Evasion

Version: 101

Rule authors:

  • Elastic

Rule license: Elastic License v2

Investigation guideedit

Rule queryedit

process where event.type == "start" and : "MSBuild.exe" and : ("csc.exe", "iexplore.exe", "powershell.exe")