BITS Transfer Job Downloading File Possible Suspicious Extension (via bits-client)

title: BITS Transfer Job Downloading File Possible Suspicious Extension (via bits-client)
id: 9f77b025-e7b7-55be-ac0c-0d1d30d08221
status: stable
description: This rule detects new BITS transfer job saving local files with potential anomalous extensions
references:
    - https://attack.mitre.org/techniques/T1197/
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1197/T1197.md
author: Huntrule Team
date: 2026-02-07
tags:
    - attack.persistence
    - attack.execution
    - attack.stealth
    - attack.t1197
logsource:
    product: windows
    service: bits-client
detection:
    selection:
        EventID: 16403
        LocalName|endswith:
            - '.bat'
            - '.dll'
            - '.exe'
            - '.hta'
            - '.ps1'
            - '.psd1'
            - '.sh'
            - '.vbe'
            - '.vbs'
    filter_optional_generic:
        LocalName|contains: '\AppData\'
        RemoteName|contains: '.com'
    condition: selection and not 1 of filter_optional_*
falsepositives:
    - Unknown
level: medium