Potentially Suspicious Network Connection To Notion API (via network_connection)

This rule detects a non-browser process communicating with the Notion API. This could indicate potential use of a covert C2 channel such as "OffensiveNotion C2"

SigmalowWindowsv1
sigma
title: Potentially Suspicious Network Connection To Notion API (via network_connection)
id: 0863f012-909e-591c-a9c5-82fe7fffeb89
status: stable
description: This rule detects a non-browser process communicating with the Notion API. This could indicate potential use of a covert C2 channel such as "OffensiveNotion C2"
references:
    - https://attack.mitre.org/techniques/T1102/
    - https://github.com/mttaggart/OffensiveNotion
    - https://medium.com/@huskyhacks.mk/we-put-a-c2-in-your-notetaking-app-offensivenotion-3e933bace332
author: Huntrule Team
date: 2026-01-06
tags:
    - attack.command-and-control
    - attack.t1102
logsource:
    product: windows
    category: network_connection
detection:
    selection:
        DestinationHostname|contains: 'api.notion.com'
    filter_main_notion:
        Image|endswith: '\AppData\Local\Programs\Notion\Notion.exe'
    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: low

Known false positives

  • Unknown

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.