blue-team-tools/rules/web/proxy_generic/proxy_ua_bitsadmin_susp_tld.yml

title: Bitsadmin to Uncommon TLD
id: 9eb68894-7476-4cd6-8752-23b51f5883a7
status: experimental
description: Detects Bitsadmin connections to domains with uncommon TLDs
references:
    - https://twitter.com/jhencinski/status/1102695118455349248
    - https://isc.sans.edu/forums/diary/Investigating+Microsoft+BITS+Activity/23281/
author: Florian Roth (Nextron Systems), Tim Shelton
date: 2019/03/07
modified: 2022/08/16
tags:
    - attack.command_and_control
    - attack.t1071.001
    - attack.defense_evasion
    - attack.persistence
    - attack.t1197
    - attack.s0190
logsource:
    category: proxy
detection:
    selection:
        c-useragent|startswith: 'Microsoft BITS/'
    falsepositives:
        r-dns|endswith:
            - '.com'
            - '.net'
            - '.org'
            - '.scdn.co' # spotify streaming
            - '.sfx.ms' # Microsoft domain, example request: https://oneclient.sfx.ms/PreSignInSettings/Prod/2022-08-15-21-xx-xx/PreSignInSettingsConfig.json
    condition: selection and not falsepositives
fields:
    - ClientIP
    - c-uri
    - c-useragent
falsepositives:
    - Rare programs that use Bitsadmin and update from regional TLDs e.g. .uk or .ca
level: high