splunk_escuHunting

Windows MSIX Package Interaction

This hunting query detects user interactions with MSIX packages by monitoring EventCode 171 in the Microsoft-Windows-AppXPackaging/Operational logs. These events are generated when a user clicks on or attempts to interact with an MSIX package, even if the package is not fully installed. This information can be valuable for security teams to identify what MSIX packages users are attempting to open in their environment, which may help detect malicious MSIX packages before they're fully installed. Monitoring these interactions can provide early warning of potential MSIX package abuse, which has been leveraged by threat actors such as FIN7, Zloader (Storm-0569), and FakeBat (Storm-1113).

MITRE ATT&CK

T1204.002

Detection Query

`wineventlog_appxpackaging` EventCode=171
  | stats count min(_time) as firstTime max(_time) as lastTime values(packageFullName) as packageFullName values(user_id) as user_id
    BY host EventCode
  | `security_content_ctime(firstTime)`
  | `security_content_ctime(lastTime)`
  | `windows_msix_package_interaction_filter`

Author

Michael Haag, Splunk

Created

2026-02-25

Data Sources

Windows Event Log AppXPackaging 171

References

Tags

MSIX Package Abuse

Raw Content

name: Windows MSIX Package Interaction
id: 1a06689d-814e-4db2-b2c7-5a174f8c2d6d
version: 2
date: '2026-02-25'
author: Michael Haag, Splunk
status: production
type: Hunting
description: This hunting query detects user interactions with MSIX packages by monitoring EventCode 171 in the Microsoft-Windows-AppXPackaging/Operational logs. These events are generated when a user clicks on or attempts to interact with an MSIX package, even if the package is not fully installed. This information can be valuable for security teams to identify what MSIX packages users are attempting to open in their environment, which may help detect malicious MSIX packages before they're fully installed. Monitoring these interactions can provide early warning of potential MSIX package abuse, which has been leveraged by threat actors such as FIN7, Zloader (Storm-0569), and FakeBat (Storm-1113).
data_source:
    - Windows Event Log AppXPackaging 171
search: |-
    `wineventlog_appxpackaging` EventCode=171
      | stats count min(_time) as firstTime max(_time) as lastTime values(packageFullName) as packageFullName values(user_id) as user_id
        BY host EventCode
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `windows_msix_package_interaction_filter`
how_to_implement: To implement this detection, you need to be collecting Windows Event logs from the Microsoft-Windows-AppXPackaging/Operational channel. In Splunk, this typically requires the Windows TA and configuration to collect from this specific channel. Ensure your Windows event collection is properly configured to capture EventCode 171 from the Microsoft-Windows-AppXPackaging/Operational log. This query is designed as a hunting query to help identify MSIX package interactions across your environment.
known_false_positives: This hunting query will detect legitimate MSIX package interactions from normal users. It is not designed to specifically identify malicious activity but rather to provide visibility into all MSIX package interactions. Security teams should review the results and look for unusual patterns, unexpected packages, or suspicious file paths.
references:
    - https://www.appdeploynews.com/packaging-types/msix/troubleshooting-an-msix-package/
    - https://learn.microsoft.com/en-us/windows/win32/appxpkg/troubleshooting
    - https://www.advancedinstaller.com/msix-installation-or-launching-errors-and-fixes.html
    - https://redcanary.com/blog/msix-installers/
tags:
    analytic_story:
        - MSIX Package Abuse
    asset_type: Endpoint
    mitre_attack_id:
        - T1204.002
    product:
        - Splunk Enterprise
        - Splunk Enterprise Security
        - Splunk Cloud
    security_domain: endpoint
    cve: []
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1204.002/appx/windows-appxpackaging.log
          sourcetype: XmlWinEventLog
          source: XmlWinEventLog:Microsoft-Windows-AppxPackaging/Operational