Detection rules › Sigma

Network Connection Initiated From Process Located In Potentially Suspicious Or Uncommon Location

Status
test
Severity
high
Log source
category network_connection, product windows
Author
Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects a network connection initiated by programs or processes running from suspicious or uncommon files system locations.

MITRE ATT&CK coverage

TacticTechniques
Command & Control

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 3: Network connection

Rule body

title: Network Connection Initiated From Process Located In Potentially Suspicious Or Uncommon Location
id: 7b434893-c57d-4f41-908d-6a17bf1ae98f
related:
    - id: 8b48ad89-10d8-4382-a546-50588c410f0d
      type: similar
    - id: d635249d-86b5-4dad-a8c7-d7272b788586
      type: similar
    - id: 52182dfb-afb7-41db-b4bc-5336cb29b464
      type: similar
    - id: ae02ed70-11aa-4a22-b397-c0d0e8f6ea99
      type: similar
    - id: e0f8ab85-0ac9-423b-a73a-81b3c7b1aa97
      type: similar
    - id: 8518ed3d-f7c9-4601-a26c-f361a4256a0c
      type: similar
    - id: 42a5f1e7-9603-4f6d-97ae-3f37d130d794
      type: similar
    - id: 56454143-524f-49fb-b1c6-3fb8b1ad41fb
      type: similar
    - id: b6e04788-29e1-4557-bb14-77f761848ab8
      type: similar
    - id: a0d7e4d2-bede-4141-8896-bc6e237e977c
      type: similar
    - id: 297ae038-edc2-4b2e-bb3e-7c5fc94dd5c7
      type: similar
status: test
description: |
    Detects a network connection initiated by programs or processes running from suspicious or uncommon files system locations.
references:
    - https://docs.google.com/spreadsheets/d/17pSTDNpa0sf6pHeRhusvWG6rThciE8CsXTSlDUAZDyo
author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
date: 2017-03-19
modified: 2026-03-29
tags:
    - attack.command-and-control
    - attack.t1105
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        Initiated: 'true'
        Image|contains:
            - ':\$Recycle.bin'
            - ':\Perflogs\'
            - ':\Temp\'
            - ':\Users\Default\'
            - ':\Users\Public\'
            - ':\Windows\Fonts\'
            - ':\Windows\IME\'
            - ':\Windows\System32\Tasks\'
            - ':\Windows\Tasks\'
            - '\config\systemprofile\'
            - '\Contacts\'
            - '\Favorites\'
            - '\Favourites\'
            - '\Music\'
            - '\Pictures\'
            - '\Videos\'
            - '\Windows\addins\'
    filter_main_domains:
        # Note: We exclude these domains to avoid duplicate filtering from e0f8ab85-0ac9-423b-a73a-81b3c7b1aa97
        DestinationHostname|endswith:
            - '.githubusercontent.com'       # Includes both gists and github repositories / Michael Haag (idea)
            - '0x0.st'
            - 'anonfiles.com'
            - 'bashupload.com'
            - 'cdn.discordapp.com'
            - 'chunk.io'
            - 'ddns.net'
            - 'dl.dropboxusercontent.com'
            - 'ghostbin.co'
            - 'github.com'
            - 'glitch.me'
            - 'gofile.io'
            - 'hastebin.com'
            - 'mediafire.com'
            - 'mega.co.nz'
            - 'mega.nz'
            - 'onrender.com'
            - 'pages.dev'
            - 'paste.ee'
            - 'pastebin.com'
            - 'pastebin.pl'
            - 'pastetext.net'
            - 'portmap.io'  # https://pro.twitter.com/JaromirHorejsi/status/1795001037746761892/photo/2
            - 'privatlab.com'
            - 'privatlab.net'
            - 'send.exploit.in'
            - 'sendspace.com'
            - 'storage.googleapis.com'
            - 'storjshare.io'
            - 'supabase.co'
            - 'temp.sh'
            - 'transfer.sh'
            - 'trycloudflare.com'
            - 'ufile.io'
            - 'w3spaces.com'
            - 'workers.dev'
            - 'x0.at'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    Initiated: 'true'
    Image|contains:
        - ':\$Recycle.bin'
        - ':\Perflogs\'
        - ':\Temp\'
        - ':\Users\Default\'
        - ':\Users\Public\'
        - ':\Windows\Fonts\'
        - ':\Windows\IME\'
        - ':\Windows\System32\Tasks\'
        - ':\Windows\Tasks\'
        - '\config\systemprofile\'
        - '\Contacts\'
        - '\Favorites\'
        - '\Favourites\'
        - '\Music\'
        - '\Pictures\'
        - '\Videos\'
        - '\Windows\addins\'

Stage 2: not filter_main_domains

filter_main_domains:
    DestinationHostname|endswith:
        - '.githubusercontent.com'
        - '0x0.st'
        - 'anonfiles.com'
        - 'bashupload.com'
        - 'cdn.discordapp.com'
        - 'chunk.io'
        - 'ddns.net'
        - 'dl.dropboxusercontent.com'
        - 'ghostbin.co'
        - 'github.com'
        - 'glitch.me'
        - 'gofile.io'
        - 'hastebin.com'
        - 'mediafire.com'
        - 'mega.co.nz'
        - 'mega.nz'
        - 'onrender.com'
        - 'pages.dev'
        - 'paste.ee'
        - 'pastebin.com'
        - 'pastebin.pl'
        - 'pastetext.net'
        - 'portmap.io'
        - 'privatlab.com'
        - 'privatlab.net'
        - 'send.exploit.in'
        - 'sendspace.com'
        - 'storage.googleapis.com'
        - 'storjshare.io'
        - 'supabase.co'
        - 'temp.sh'
        - 'transfer.sh'
        - 'trycloudflare.com'
        - 'ufile.io'
        - 'w3spaces.com'
        - 'workers.dev'
        - 'x0.at'

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
DestinationHostnameends_with.githubusercontent.comexcludes:DestinationHostname field:"DestinationHostname" value:".githubusercontent.com"
DestinationHostnameends_with0x0.stexcludes:DestinationHostname field:"DestinationHostname" value:"0x0.st"
DestinationHostnameends_withanonfiles.comexcludes:DestinationHostname field:"DestinationHostname" value:"anonfiles.com"
DestinationHostnameends_withbashupload.comexcludes:DestinationHostname field:"DestinationHostname" value:"bashupload.com"
DestinationHostnameends_withcdn.discordapp.comexcludes:DestinationHostname field:"DestinationHostname" value:"cdn.discordapp.com"
DestinationHostnameends_withchunk.ioexcludes:DestinationHostname field:"DestinationHostname" value:"chunk.io"
DestinationHostnameends_withddns.netexcludes:DestinationHostname field:"DestinationHostname" value:"ddns.net"
DestinationHostnameends_withdl.dropboxusercontent.comexcludes:DestinationHostname field:"DestinationHostname" value:"dl.dropboxusercontent.com"
DestinationHostnameends_withghostbin.coexcludes:DestinationHostname field:"DestinationHostname" value:"ghostbin.co"
DestinationHostnameends_withgithub.comexcludes:DestinationHostname field:"DestinationHostname" value:"github.com"
DestinationHostnameends_withglitch.meexcludes:DestinationHostname field:"DestinationHostname" value:"glitch.me"
DestinationHostnameends_withgofile.ioexcludes:DestinationHostname field:"DestinationHostname" value:"gofile.io"
DestinationHostnameends_withhastebin.comexcludes:DestinationHostname field:"DestinationHostname" value:"hastebin.com"
DestinationHostnameends_withmediafire.comexcludes:DestinationHostname field:"DestinationHostname" value:"mediafire.com"
DestinationHostnameends_withmega.co.nzexcludes:DestinationHostname field:"DestinationHostname" value:"mega.co.nz"
DestinationHostnameends_withmega.nzexcludes:DestinationHostname field:"DestinationHostname" value:"mega.nz"
DestinationHostnameends_withonrender.comexcludes:DestinationHostname field:"DestinationHostname" value:"onrender.com"
DestinationHostnameends_withpages.devexcludes:DestinationHostname field:"DestinationHostname" value:"pages.dev"
DestinationHostnameends_withpaste.eeexcludes:DestinationHostname field:"DestinationHostname" value:"paste.ee"
DestinationHostnameends_withpastebin.comexcludes:DestinationHostname field:"DestinationHostname" value:"pastebin.com"
DestinationHostnameends_withpastebin.plexcludes:DestinationHostname field:"DestinationHostname" value:"pastebin.pl"
DestinationHostnameends_withpastetext.netexcludes:DestinationHostname field:"DestinationHostname" value:"pastetext.net"
DestinationHostnameends_withportmap.ioexcludes:DestinationHostname field:"DestinationHostname" value:"portmap.io"
DestinationHostnameends_withprivatlab.comexcludes:DestinationHostname field:"DestinationHostname" value:"privatlab.com"
DestinationHostnameends_withprivatlab.netexcludes:DestinationHostname field:"DestinationHostname" value:"privatlab.net"
DestinationHostnameends_withsend.exploit.inexcludes:DestinationHostname field:"DestinationHostname" value:"send.exploit.in"
DestinationHostnameends_withsendspace.comexcludes:DestinationHostname field:"DestinationHostname" value:"sendspace.com"
DestinationHostnameends_withstorage.googleapis.comexcludes:DestinationHostname field:"DestinationHostname" value:"storage.googleapis.com"
DestinationHostnameends_withstorjshare.ioexcludes:DestinationHostname field:"DestinationHostname" value:"storjshare.io"
DestinationHostnameends_withsupabase.coexcludes:DestinationHostname field:"DestinationHostname" value:"supabase.co"
DestinationHostnameends_withtemp.shexcludes:DestinationHostname field:"DestinationHostname" value:"temp.sh"
DestinationHostnameends_withtransfer.shexcludes:DestinationHostname field:"DestinationHostname" value:"transfer.sh"
DestinationHostnameends_withtrycloudflare.comexcludes:DestinationHostname field:"DestinationHostname" value:"trycloudflare.com"
DestinationHostnameends_withufile.ioexcludes:DestinationHostname field:"DestinationHostname" value:"ufile.io"
DestinationHostnameends_withw3spaces.comexcludes:DestinationHostname field:"DestinationHostname" value:"w3spaces.com"
DestinationHostnameends_withworkers.devexcludes:DestinationHostname field:"DestinationHostname" value:"workers.dev"
DestinationHostnameends_withx0.atexcludes:DestinationHostname field:"DestinationHostname" value:"x0.at"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imagematch
  • :\$Recycle.bin corpus 2 (sigma 2)
  • :\Perflogs\ corpus 9 (sigma 9)
  • :\Temp\ corpus 11 (sigma 11)
  • :\Users\Default\ corpus 3 (sigma 3)
  • :\Users\Public\ corpus 13 (sigma 13)
  • :\Windows\Fonts\ corpus 3 (sigma 3)
  • :\Windows\IME\ corpus 3 (sigma 3)
  • :\Windows\System32\Tasks\ corpus 4 (sigma 4)
  • :\Windows\Tasks\ corpus 4 (sigma 4)
  • \Contacts\ corpus 4 (sigma 4)
  • \Favorites\ corpus 5 (sigma 5)
  • \Favourites\ corpus 4 (sigma 4)
  • \Music\ corpus 3 (sigma 3)
  • \Pictures\ corpus 4 (sigma 4)
  • \Videos\ corpus 3 (sigma 3)
  • \Windows\addins\ corpus 4 (sigma 4)
  • \config\systemprofile\ corpus 4 (sigma 4)
field:"Image" kind:match
Initiatedeq
  • true corpus 50 (sigma 50)
field:"Initiated" kind:eq value:"true"