Windows Process Execution: SyncAppvPublishingServer.exe With PowerShell Injection Pattern

Alerts when SyncAppvPublishingServer.exe is launched with a command-line pattern indicative of PowerShell code execution.

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windows-process-execution-syncappvpublishingserver-exe-with-powershell-injection-fbd7c32d

title: "Windows Process Execution: SyncAppvPublishingServer.exe With PowerShell Injection Pattern"
id: fba39b26-a16b-444a-aa78-8dae9cd323b5
related:
  - id: fde7929d-8beb-4a4c-b922-be9974671667
    type: obsolete
  - id: fbd7c32d-db2a-4418-b92c-566eb8911133
    type: derived
status: test
description: This rule flags process creation of SyncAppvPublishingServer.exe when its command line contains a PowerShell injection-style substring ("n; ). Attackers can abuse legitimate Windows/App-V related binaries to execute arbitrary PowerShell while blending into expected software activity. It relies on Windows process creation telemetry, matching both the executable identity (path ending or original file name) and the specific command-line pattern.
references:
  - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1218/T1218.md
  - https://lolbas-project.github.io/lolbas/Binaries/Syncappvpublishingserver/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_lolbin_syncappvpublishingserver_execute_psh.yml
author: frack113, Huntrule Team
date: 2021-07-12
modified: 2022-10-04
tags:
  - attack.stealth
  - attack.t1218
logsource:
  category: process_creation
  product: windows
detection:
  selection_img:
    - Image|endswith: \SyncAppvPublishingServer.exe
    - OriginalFileName: syncappvpublishingserver.exe
  selection_cli:
    CommandLine|contains: '"n; '
  condition: all of selection_*
falsepositives:
  - App-V clients
level: medium
license: DRL-1.1

What it detects

This rule flags process creation of SyncAppvPublishingServer.exe when its command line contains a PowerShell injection-style substring ("n; ). Attackers can abuse legitimate Windows/App-V related binaries to execute arbitrary PowerShell while blending into expected software activity. It relies on Windows process creation telemetry, matching both the executable identity (path ending or original file name) and the specific command-line pattern.

Known false positives

App-V clients

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.