Suspicious Non-Browser Network Traffic With Telegram API (via network_connection)

title: Suspicious Non-Browser Network Traffic With Telegram API (via network_connection)
id: 8269acaf-2223-5b91-b61c-7a0b3062ed59
status: stable
description: This rule detects an a non-browser process interacting with the Telegram API which could indicate use of a covert C2
references:
    - https://attack.mitre.org/techniques/T1105/
    - https://attack.mitre.org/techniques/T1567/
    - https://attack.mitre.org/techniques/T1102/
    - https://www.ncsc.gov.uk/static-assets/documents/malware-analysis-reports/small-sieve/NCSC-MAR-Small-Sieve.pdf
author: Huntrule Team
date: 2026-04-05
tags:
    - attack.command-and-control
    - attack.exfiltration
    - attack.t1102
    - attack.t1567
    - attack.t1105
logsource:
    product: windows
    category: network_connection
detection:
    selection:
        DestinationHostname|contains: 'api.telegram.org'
    filter_main_brave:
        Image|endswith: '\brave.exe'
    filter_main_chrome:
        Image:
            - 'C:\Program Files\Google\Chrome\Application\chrome.exe'
            - 'C:\Program Files (x86)\Google\Chrome\Application\chrome.exe'
    filter_main_firefox:
        Image:
            - 'C:\Program Files\Mozilla Firefox\firefox.exe'
            - 'C:\Program Files (x86)\Mozilla Firefox\firefox.exe'
    filter_main_ie:
        Image:
            - 'C:\Program Files (x86)\Internet Explorer\iexplore.exe'
            - 'C:\Program Files\Internet Explorer\iexplore.exe'
    filter_main_maxthon:
        Image|endswith: '\maxthon.exe'
    filter_main_edge_1:
        - Image|startswith: 'C:\Program Files (x86)\Microsoft\EdgeWebView\Application\'
        - Image|endswith: '\WindowsApps\MicrosoftEdge.exe'
        - Image:
              - 'C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe'
              - 'C:\Program Files\Microsoft\Edge\Application\msedge.exe'
    filter_main_edge_2:
        Image|startswith:
            - 'C:\Program Files (x86)\Microsoft\EdgeCore\'
            - 'C:\Program Files\Microsoft\EdgeCore\'
        Image|endswith:
            - '\msedge.exe'
            - '\msedgewebview2.exe'
    filter_main_opera:
        Image|endswith: '\opera.exe'
    filter_main_safari:
        Image|endswith: '\safari.exe'
    filter_main_seamonkey:
        Image|endswith: '\seamonkey.exe'
    filter_main_vivaldi:
        Image|endswith: '\vivaldi.exe'
    filter_main_whale:
        Image|endswith: '\whale.exe'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium