Microsoft Build Engine Started by a Script Process

Elastic Stack Serverless Security

An instance of MSBuild, the Microsoft Build Engine, was started by a script or the Windows command interpreter. This behavior is unusual and is sometimes used by malicious payloads.

Rule type: eql

Rule indices:

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

Severity: low

Risk score: 21

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References: None

Tags:

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

Version: 10

Rule authors:

• Elastic

Rule license: Elastic License v2

process where event.type == "start" and
  (process.name : "MSBuild.exe" or process.pe.original_file_name == "MSBuild.exe") and
  process.parent.name : ("cmd.exe", "powershell.exe", "pwsh.exe", "powershell_ise.exe", "cscript.exe", "wscript.exe", "mshta.exe")

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Defense Evasion
  • ID: TA0005
  • Reference URL: https://attack.mitre.org/tactics/TA0005/

• Technique:

  • Name: Trusted Developer Utilities Proxy Execution
  • ID: T1127
  • Reference URL: https://attack.mitre.org/techniques/T1127/

• Sub-technique:

  • Name: MSBuild
  • ID: T1127.001
  • Reference URL: https://attack.mitre.org/techniques/T1127/001/

• Tactic:

  • Name: Execution
  • ID: TA0002
  • Reference URL: https://attack.mitre.org/tactics/TA0002/