IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
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: query
Rule indices:
- winlogbeat-*
Severity: low
Risk score: 21
Runs every: 5 minutes
Searches indices from: now-6m (Date Math format, see also Additional look-back time
)
Maximum signals per execution: 100
References:
Tags:
- Elastic
- Windows
Version: 1
Added (Elastic Stack release): 7.7.0
Potential false positivesedit
The Build Engine is commonly used by Windows developers but use by non-engineers is unusual. If a build system triggers this rule it can be exempted by process, user, or host name.
Rule queryedit
process.parent.name:MSBuild.exe and process.name:(csc.exe or iexplore.exe or powershell.exe)
Threat mappingedit
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: Compile After Delivery
- ID: T1500
- Reference URL: https://attack.mitre.org/techniques/T1500/