Detection: Windows AppX Deployment Package Installation Success

Updated Date: 2025-08-05 ID: 1234abcd-5678-90ef-1234-56789abcdef0 Author: Michael Haag, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

This analytic detects successful MSIX/AppX package installations on Windows systems by monitoring EventID 854 in the Microsoft-Windows-AppXDeployment-Server/Operational log. This event is generated when an MSIX/AppX package has been successfully installed on a system. While most package installations are legitimate, monitoring these events can help identify unauthorized or suspicious package installations, especially when correlated with other events such as unsigned package installations (EventID 603 with Flags=8388608) or full trust package installations (EventID 400 with HasFullTrust=true).

Search

1`wineventlog_appxdeploymentserver` EventCode=854 
2| stats count min(_time) as firstTime max(_time) as lastTime values(Path) as PackagePath by dvc EventCode user_id 
3| rename dvc as dest 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `windows_appx_deployment_package_installation_success_filter`

Data Source

Name	Platform	Sourcetype	Source
Windows Event Log AppXDeployment-Server 854	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Microsoft-Windows-AppXDeploymentServer/Operational'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
windows_appx_deployment_package_installation_success_filter	`search *`

windows_appx_deployment_package_installation_success_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1204.002	Malicious File	Execution

Installation

DE.AE

CIS 10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Risk Event	True

This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

To implement this detection, you need to be collecting Windows Event Logs from your endpoints, specifically the Microsoft-Windows-AppXDeploymentServer/Operational log. Ensure that your Splunk deployment is ingesting these logs with the source type "XmlWinEventLog:Microsoft-Windows-AppXDeploymentServer/Operational". This detection works best when used in conjunction with other MSIX package abuse detections such as unsigned package installations (EventID 603) and full trust package installations (EventID 400).

Known False Positives

Legitimate MSIX/AppX package installations will trigger this detection. This is expected behavior and not necessarily indicative of malicious activity. This analytic is designed to provide visibility into package installations and should be used as part of a broader detection strategy. Consider correlating these events with other suspicious indicators such as unsigned packages or packages from unusual sources.

Associated Analytic Story

MSIX Package Abuse

Risk Based Analytics (RBA)

Risk Message:

A MSIX/AppX package $PackagePath$ was successfully installed on $dest$ by user $user_id$.

Risk Object	Risk Object Type	Risk Score	Threat Objects
dest	system	10	PackagePath

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-AppXDeploymentServer/Operational`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-AppXDeploymentServer/Operational`	`XmlWinEventLog`

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 1