Microsoft Build Engine Started by a System Process

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An instance of MSBuild, the Microsoft Build Engine, was started by Explorer or the WMI (Windows Management Instrumentation) subsystem. This behavior is unusual and is sometimes used by malicious payloads.

Rule type: query

Rule indices:

  • winlogbeat-*
  • logs-endpoint.events.*

Severity: medium

Risk score: 47

Runs every: 5 minutes

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

Maximum alerts per execution: 100

Tags:

  • Elastic
  • Windows

Version: 3 (version history)

Added (Elastic Stack release): 7.7.0

Last modified (Elastic Stack release): 7.9.1

Rule authors: Elastic

Rule license: Elastic License

Potential false positives

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The Build Engine is commonly used by Windows developers but use by non-engineers is unusual.

Rule query

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event.category:process and event.type:(start or process_started) and
process.name:MSBuild.exe and process.parent.name:(explorer.exe or
wmiprvse.exe)

Threat mapping

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Framework: MITRE ATT&CKTM

Rule version history

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Version 3 (7.9.1 release)
  • Formatting only
Version 2 (7.9.0 release)
  • Updated query, changed from:

    process.name:MSBuild.exe and process.parent.name:(explorer.exe or
    wmiprvse.exe) and event.action:"Process Create (rule: ProcessCreate)"