Suspicious Unblock-File (via ps_script)

title: Suspicious Unblock-File (via ps_script)
id: b7222a68-6aef-51b5-b1c3-ef2dd7c34b81
status: stable
description: This rule detects the Zone.Identifier alternate data stream which flags the file as downloaded from the internet.
references:
    - https://attack.mitre.org/techniques/T1553/005/
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1553.005/T1553.005.md#atomic-test-3---remove-the-zoneidentifier-alternate-data-stream
    - https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/unblock-file?view=powershell-7.2
author: Huntrule Team
date: 2026-06-03
tags:
    - attack.defense-impairment
    - attack.t1553.005
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|contains|all:
            - 'Unblock-File '
            - '-Path '
    condition: selection
falsepositives:
    - Unknown
level: medium