Suspicious New-PSDrive to Admin Share

SIGMA detection rule by frack113 · NOASSERTION

Adversaries may use to interact with a remote network share using Server Message Block (SMB). The adversary may then perform actions as the logged-on user.

title: Suspicious New-PSDrive to Admin Share
id: 1c563233-030e-4a07-af8c-ee0490a66d3a
status: test
description: Adversaries may use to interact with a remote network share using Server Message Block (SMB). The adversary may then perform actions as the logged-on user.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1021.002/T1021.002.md#atomic-test-2---map-admin-share-powershell
    - https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.management/new-psdrive?view=powershell-7.2
author: frack113
date: 2022-08-13
tags:
    - attack.lateral-movement
    - attack.t1021.002
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|contains|all:
            - 'New-PSDrive'
            - '-psprovider '
            - 'filesystem'
            - '-root '
            - '\\\\'
            - '$'
    condition: selection
falsepositives:
    - Unknown
level: medium
regression_tests_path: regression_data/rules/windows/powershell/powershell_script/posh_ps_susp_new_psdrive/info.yml

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

b5416c94-e31c-43e8-9697-7c919294583d

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This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

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