SigmaHQ/rules/windows/process_creation/win_susp_desktopimgdownldr.yml

title: Suspicious Desktopimgdownldr Command
id: bb58aa4a-b80b-415a-a2c0-2f65a4c81009
status: experimental
description: Detects a suspicious Microsoft desktopimgdownldr execution with parameters used to download files from the Internet
author: Florian Roth
date: 2020/07/03
references:
    - https://labs.sentinelone.com/living-off-windows-land-a-new-native-file-downldr/
logsource:
    category: process_creation
    product: windows
tags:
    - attack.defense_evasion
    - attack.t1105
detection:
    selection1:
        CommandLine|contains: ' /lockscreenurl:'
    selection2_filter:
        CommandLine|contains:
            - '.jpg'
            - '.jpeg'
            - '.png'
    selection_reg:
        CommandLine|contains|all:
            - 'reg delete'
            - '\PersonalizationCSP'
    condition: selection1 and not selection1_filter or selection_reg
fields:
    - CommandLine
    - ParentCommandLine
falsepositives:
    - False positives depend on scripts and administrative tools used in the monitored environment
level: high