Sigma rule: New Connection Initiated To Potential Dead Drop Resolver Domain

Rule

Title

New Connection Initiated To Potential Dead Drop Resolver Domain

Status

test

Level

high

Author

Sorina Ionescu, X__Junior (Nextron Systems)

Date

2022-08-17

Modified

2026-03-29

File

rules/windows/network_connection/net_connection_win_domain_dead_drop_resolvers.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects an executable, which is not an internet browser or known application, initiating network connections to legit popular websites, which were seen to be used as dead drop resolvers in previous attacks.
In this context attackers leverage known websites such as "facebook", "youtube", etc. In order to pass through undetected.

Log source

product

windows

category

network_connection

Detection

selection:
    Initiated: 'true'
    DestinationHostname|endswith:
        - '.t.me'
        - '0x0.st'
        - '4shared.com'
        - 'abuse.ch'
        - 'anonfiles.com'
        - 'bashupload.com'
        - 'cdn.discordapp.com'
        - 'chunk.io'
        - 'cloudflare.com'
        - 'ddns.net'
        - 'discord.com'
        - 'docs.google.com'
        - 'drive.google.com'
        - 'dropbox.com'
        - 'dropmefiles.com'
        - 'facebook.com'
        - 'feeds.rapidfeeds.com'
        - 'fotolog.com'
        - 'ghostbin.co/'
        - 'githubusercontent.com'
        - 'gofile.io'
        - 'hastebin.com'
        - 'imgur.com'
        - 'livejournal.com'
        - 'mediafire.com'
        - 'mega.co.nz'
        - 'mega.nz'
        - 'onedrive.com'
        - 'pages.dev'
        - 'paste.ee'
        - 'pastebin.com'
        - 'pastebin.pl'
        - 'pastetext.net'
        - 'pixeldrain.com'
        - 'privatlab.com'
        - 'privatlab.net'
        - 'reddit.com'
        - 'send.exploit.in'
        - 'sendspace.com'
        - 'steamcommunity.com'
        - 'storage.googleapis.com'
        - 'technet.microsoft.com'
        - 'temp.sh'
        - 'transfer.sh'
        - 'trycloudflare.com'
        - 'twitter.com'
        - 'ufile.io'
        - 'vimeo.com'
        - 'w3spaces.com'
        - 'wetransfer.com'
        - 'workers.dev'
        - 'x0.at'
        - 'youtube.com'
# Note: Add/Remove browsers/applications that you don't use or those that have custom install locations
# Note: To avoid complex conditions the filters for some apps are generic by name only. A custom tuning is recommended for best results
filter_main_chrome:
    Image:
        - 'C:\Program Files\Google\Chrome\Application\chrome.exe'
        - 'C:\Program Files (x86)\Google\Chrome\Application\chrome.exe'
filter_main_chrome_appdata:
    Image|startswith: 'C:\Users\'
    Image|endswith: '\AppData\Local\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_firefox_appdata:
    Image|startswith: 'C:\Users\'
    Image|endswith: '\AppData\Local\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_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_safari:
    Image|contains:
        - 'C:\Program Files (x86)\Safari\'
        - 'C:\Program Files\Safari\'
    Image|endswith: '\safari.exe'
filter_main_defender:
    Image|contains:
        - 'C:\Program Files\Windows Defender Advanced Threat Protection\'
        - 'C:\Program Files\Windows Defender\'
        - 'C:\ProgramData\Microsoft\Windows Defender\Platform\'
    Image|endswith:
        - '\MsMpEng.exe' # Microsoft Defender executable
        - '\MsSense.exe' # Windows Defender Advanced Threat Protection Service Executable
filter_main_prtg:
    # Paessler's PRTG Network Monitor
    Image|endswith:
        - 'C:\Program Files (x86)\PRTG Network Monitor\PRTG Probe.exe'
        - 'C:\Program Files\PRTG Network Monitor\PRTG Probe.exe'
filter_main_brave:
    Image|startswith: 'C:\Program Files\BraveSoftware\'
    Image|endswith: '\brave.exe'
filter_main_maxthon:
    Image|contains: '\AppData\Local\Maxthon\'
    Image|endswith: '\maxthon.exe'
filter_main_opera:
    Image|contains: '\AppData\Local\Programs\Opera\'
    Image|endswith: '\opera.exe'
filter_main_seamonkey:
    Image|startswith:
        - 'C:\Program Files\SeaMonkey\'
        - 'C:\Program Files (x86)\SeaMonkey\'
    Image|endswith: '\seamonkey.exe'
filter_main_vivaldi:
    Image|contains: '\AppData\Local\Vivaldi\'
    Image|endswith: '\vivaldi.exe'
filter_main_whale:
    Image|startswith:
        - 'C:\Program Files\Naver\Naver Whale\'
        - 'C:\Program Files (x86)\Naver\Naver Whale\'
    Image|endswith: '\whale.exe'
# Note: The TOR browser shouldn't be something you allow in your corporate network.
# filter_main_tor:
#     Image|contains: '\Tor Browser\'
filter_main_whaterfox:
    Image|startswith:
        - 'C:\Program Files\Waterfox\'
        - 'C:\Program Files (x86)\Waterfox\'
    Image|endswith: '\Waterfox.exe'
filter_main_midori:
    Image|contains: '\AppData\Local\Programs\midori-ng\'
    Image|endswith: '\Midori Next Generation.exe'
filter_main_slimbrowser:
    Image|startswith:
        - 'C:\Program Files\SlimBrowser\'
        - 'C:\Program Files (x86)\SlimBrowser\'
    Image|endswith: '\slimbrowser.exe'
filter_main_flock:
    Image|contains: '\AppData\Local\Flock\'
    Image|endswith: '\Flock.exe'
filter_main_phoebe:
    Image|contains: '\AppData\Local\Phoebe\'
    Image|endswith: '\Phoebe.exe'
filter_main_falkon:
    Image|startswith:
        - 'C:\Program Files\Falkon\'
        - 'C:\Program Files (x86)\Falkon\'
    Image|endswith: '\falkon.exe'
filter_main_qtweb:
    Image|startswith:
        - 'C:\Program Files (x86)\QtWeb\'
        - 'C:\Program Files\QtWeb\'
    Image|endswith: '\QtWeb.exe'
filter_main_avant:
    Image|startswith:
        - 'C:\Program Files (x86)\Avant Browser\'
        - 'C:\Program Files\Avant Browser\'
    Image|endswith: '\avant.exe'
filter_main_whatsapp:
    Image|startswith:
        - 'C:\Program Files (x86)\WindowsApps\'
        - 'C:\Program Files\WindowsApps\'
    Image|endswith: '\WhatsApp.exe'
    DestinationHostname|endswith: 'facebook.com'
filter_main_telegram:
    Image|contains: '\AppData\Roaming\Telegram Desktop\'
    Image|endswith: '\Telegram.exe'
    DestinationHostname|endswith: '.t.me'
filter_main_onedrive:
    Image|contains: '\AppData\Local\Microsoft\OneDrive\'
    Image|endswith: '\OneDrive.exe'
    DestinationHostname|endswith: 'onedrive.com'
filter_main_dropbox:
    Image|startswith:
        - 'C:\Program Files (x86)\Dropbox\Client\'
        - 'C:\Program Files\Dropbox\Client\'
    Image|endswith:
        - '\Dropbox.exe'
        - '\DropboxInstaller.exe'
    DestinationHostname|endswith: 'dropbox.com'
filter_main_mega:
    Image|endswith:
        # Note: This is a basic/best effort filter in order to avoid FP with the MEGA installer and executable.
        #       In practice please apply exact path to avoid basic path bypass techniques.
        - '\MEGAsync.exe'
        - '\MEGAsyncSetup32_*RC.exe' # Beta versions
        - '\MEGAsyncSetup32.exe' # Installers 32bit
        - '\MEGAsyncSetup64.exe' # Installers 64bit
        - '\MEGAupdater.exe'
    DestinationHostname|endswith:
        - 'mega.co.nz'
        - 'mega.nz'
filter_main_googledrive:
    Image|contains:
        - 'C:\Program Files\Google\Drive File Stream\'
        - 'C:\Program Files (x86)\Google\Drive File Stream\'
    Image|endswith: 'GoogleDriveFS.exe'
    DestinationHostname|endswith: 'drive.google.com'
filter_main_discord:
    Image|contains: '\AppData\Local\Discord\'
    Image|endswith: '\Discord.exe'
    DestinationHostname|endswith:
        - 'discord.com'
        - 'cdn.discordapp.com'
filter_main_null:
    Image: null
filter_main_empty:
    Image: ''
# filter_optional_qlik:
#     Image|endswith: '\Engine.exe' # Process from qlik.com app
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

• One might need to exclude other internet browsers found in it's network or other applications like ones mentioned above from Microsoft Defender.
• Ninite contacting githubusercontent.com

Tags

• attack.command-and-control
• attack.t1102
• attack.t1102.001

MITRE ATT&CK ids this rule names

• T1102
• T1102.001

Related rules

• d7b09985-95a3-44be-8450-b6eadf49833e (obsolete)
• 8b48ad89-10d8-4382-a546-50588c410f0d (similar)
• d635249d-86b5-4dad-a8c7-d7272b788586 (similar)
• 52182dfb-afb7-41db-b4bc-5336cb29b464 (similar)
• ae02ed70-11aa-4a22-b397-c0d0e8f6ea99 (similar)
• e0f8ab85-0ac9-423b-a73a-81b3c7b1aa97 (similar)
• 7b434893-c57d-4f41-908d-6a17bf1ae98f (similar)
• 8518ed3d-f7c9-4601-a26c-f361a4256a0c (similar)
• 42a5f1e7-9603-4f6d-97ae-3f37d130d794 (similar)
• 56454143-524f-49fb-b1c6-3fb8b1ad41fb (similar)
• b6e04788-29e1-4557-bb14-77f761848ab8 (similar)
• a0d7e4d2-bede-4141-8896-bc6e237e977c (similar)

References

• https://web.archive.org/web/20220830134315/https://content.fireeye.com/apt-41/rpt-apt41/
• https://securelist.com/the-tetrade-brazilian-banking-malware/97779/
• https://blog.bushidotoken.net/2021/04/dead-drop-resolvers-espionage-inspired.html
• https://github.com/kleiton0x00/RedditC2
• https://twitter.com/kleiton0x7e/status/1600567316810551296
• https://www.linkedin.com/posts/kleiton-kurti_github-kleiton0x00redditc2-abusing-reddit-activity-7009939662462984192-5DbI/?originalSubdomain=al

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/network_connection/net_connection_win_domain_dead_drop_resolvers.yml