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 Process
editMicrosoft Build Engine Started an Unusual Process
editAn instance of the Microsoft Build Engine (MSBuild) started a PowerShell script or the Visual C# command line compiler. This technique is sometimes used to deploy a malicious payload using MSBuild.
Rule type: eql
Rule indices:
- winlogbeat-*
- logs-endpoint.events.*
- 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
References:
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Defense Evasion
Version: 9
Rule authors:
- Elastic
Rule license: Elastic License v2
Investigation guide
edit## Config If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.
Rule query
editprocess where event.type in ("start", "process_started") and
process.parent.name : "MSBuild.exe" and
process.name : ("csc.exe", "iexplore.exe", "powershell.exe")
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: Obfuscated Files or Information
- ID: T1027
- Reference URL: https://attack.mitre.org/techniques/T1027/
-
Sub-technique:
- Name: Compile After Delivery
- ID: T1027.004
- Reference URL: https://attack.mitre.org/techniques/T1027/004/