Detection rules › Sigma

Remote Thread Creation By Uncommon Source Image

Status
test
Severity
medium
Log source
product windows, category create_remote_thread
Author
Perez Diego (@darkquassar), oscd.community
Source
github.com/SigmaHQ/sigma

Detects uncommon processes creating remote threads.

MITRE ATT&CK coverage

TacticTechniques
Privilege EscalationT1055 Process Injection
StealthT1055 Process Injection

Event coverage

ProviderEventTitle
SysmonEvent ID 8CreateRemoteThread

Rule body yaml

title: Remote Thread Creation By Uncommon Source Image
id: 66d31e5f-52d6-40a4-9615-002d3789a119
related:
    - id: 02d1d718-dd13-41af-989d-ea85c7fab93f
      type: derived
status: test
description: Detects uncommon processes creating remote threads.
references:
    - Personal research, statistical analysis
    - https://lolbas-project.github.io
author: Perez Diego (@darkquassar), oscd.community
date: 2019-10-27
modified: 2025-07-08
tags:
    - attack.privilege-escalation
    - attack.stealth
    - attack.t1055
logsource:
    product: windows
    category: create_remote_thread
detection:
    selection:
        SourceImage|endswith:
            - '\explorer.exe'
            - '\iexplore.exe'
            - '\msiexec.exe'
            - '\powerpnt.exe'
            - '\schtasks.exe'
            - '\winlogon.exe'
    filter_main_winlogon_1:
        SourceImage: 'C:\Windows\System32\winlogon.exe'
        TargetImage:
            - 'C:\Windows\System32\services.exe' # happens on Windows 7
            - 'C:\Windows\System32\wininit.exe' # happens on Windows 7
            - 'C:\Windows\System32\csrss.exe' # multiple OS
            - 'C:\Windows\System32\LogonUI.exe' # multiple OS
            - 'C:\Windows\System32\wlrmdr.exe'
            - 'C:\Windows\System32\AtBroker.exe'
            - 'C:\Windows\System32\dwm.exe'
            - 'C:\Windows\System32\fontdrvhost.exe'
            - 'C:\Windows\System32\userinit.exe'
    filter_main_winlogon_2:
        SourceImage: 'C:\Windows\System32\winlogon.exe'
        TargetParentProcessId: 4
    filter_main_schtasks_conhost:
        SourceImage:
            - 'C:\Windows\System32\schtasks.exe'
            - 'C:\Windows\SysWOW64\schtasks.exe'
        TargetImage: 'C:\Windows\System32\conhost.exe'
    filter_main_explorer:
        SourceImage: 'C:\Windows\explorer.exe'
        TargetImage|startswith:
            - 'C:\Program Files (x86)\'
            - 'C:\Program Files\'
            - 'C:\Windows\System32\'
            - 'C:\Windows\SysWOW64\'
    filter_main_system:
        TargetImage: 'System'
    filter_main_msiexec_1:
        # Note: MSI installers will trigger this
        SourceImage|endswith: '\msiexec.exe'
        TargetImage|contains:
            - '\AppData\Local\'
            - 'C:\Program Files (x86)\'
            - 'C:\Program Files\'
            - 'C:\Windows\Microsoft.NET\Framework64\' # C:\Windows\Microsoft.NET\Framework\v4.0.30319\ngen.exe
    filter_main_msiexec_2:
        SourceImage|endswith: '\msiexec.exe'
        TargetImage:
            - 'C:\Windows\System32\msiexec.exe'
            - 'C:\Windows\SysWOW64\msiexec.exe'
    filter_main_iexplore:
        SourceImage: 'C:\Program Files\Internet Explorer\iexplore.exe'
        TargetImage:
            - 'C:\Program Files (x86)\Internet Explorer\iexplore.exe'
            - 'C:\Windows\System32\rundll32.exe'
    filter_main_powerpnt:
        SourceImage|endswith: '\POWERPNT.EXE'
        TargetImage|contains:
            - 'C:\Program Files\Microsoft Office\' # C:\Program Files\Microsoft Office\root\vfs\ProgramFilesCommonX64\Microsoft Shared\Office16\AI\ai.exe
            - 'C:\Program Files (x86)\Microsoft Office\'
    filter_optional_aurora_smartconsole1:
        SourceImage: 'C:\Program Files\internet explorer\iexplore.exe'
        SourceCommandLine|contains|all:
            - 'https://'
            - '.checkpoint.com/documents/'
            - 'SmartConsole_OLH/'
            - 'default.htm#cshid='
    filter_optional_aurora_smartconsole2:
        SourceImage: 'C:\Program Files\internet explorer\iexplore.exe'
        SourceParentImage|startswith:
            - 'C:\Program Files\'
            - 'C:\Program Files (x86)\'
        SourceParentImage|contains|all:
            - '\CheckPoint\SmartConsole\'
            - '\SmartConsole.exe'
    filter_optional_powerpnt:
        # Raised by the following issue: https://github.com/SigmaHQ/sigma/issues/2479
        SourceImage|contains: '\Microsoft Office\'
        SourceImage|endswith: '\POWERPNT.EXE'
        TargetImage: 'C:\Windows\System32\csrss.exe'
    filter_main_null:
        TargetImage: null
    filter_main_empty:
        TargetImage: ''
    filter_optional_onedrive:
        SourceImage: 'C:\Windows\explorer.exe'
        TargetImage|endswith: '\AppData\Local\Microsoft\OneDrive\OneDrive.exe'
    filter_optional_aurora:
        SourceImage: 'C:\Windows\explorer.exe'
        TargetImage|endswith: '\aurora-dashboard.exe'
    filter_optional_officesetup:
        SourceImage: 'C:\Windows\explorer.exe'
        TargetImage|endswith: '\OfficeSetup.exe'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - This rule is best put in testing first in order to create a baseline that reflects the data in your environment.
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_* and not 1 of filter_optional_*

Stage 1: selection

selection:
    SourceImage|endswith:
        - '\explorer.exe'
        - '\iexplore.exe'
        - '\msiexec.exe'
        - '\powerpnt.exe'
        - '\schtasks.exe'
        - '\winlogon.exe'

Stage 2: not filter_main_*

filter_main_winlogon_1:
    SourceImage: 'C:\Windows\System32\winlogon.exe'
    TargetImage:
        - 'C:\Windows\System32\services.exe'
        - 'C:\Windows\System32\wininit.exe'
        - 'C:\Windows\System32\csrss.exe'
        - 'C:\Windows\System32\LogonUI.exe'
        - 'C:\Windows\System32\wlrmdr.exe'
        - 'C:\Windows\System32\AtBroker.exe'
        - 'C:\Windows\System32\dwm.exe'
        - 'C:\Windows\System32\fontdrvhost.exe'
        - 'C:\Windows\System32\userinit.exe'
filter_main_winlogon_2:
    SourceImage: 'C:\Windows\System32\winlogon.exe'
    TargetParentProcessId: 4
filter_main_schtasks_conhost:
    SourceImage:
        - 'C:\Windows\System32\schtasks.exe'
        - 'C:\Windows\SysWOW64\schtasks.exe'
    TargetImage: 'C:\Windows\System32\conhost.exe'
filter_main_explorer:
    SourceImage: 'C:\Windows\explorer.exe'
    TargetImage|startswith:
        - 'C:\Program Files (x86)\'
        - 'C:\Program Files\'
        - 'C:\Windows\System32\'
        - 'C:\Windows\SysWOW64\'
filter_main_system:
    TargetImage: 'System'
filter_main_msiexec_1:
    SourceImage|endswith: '\msiexec.exe'
    TargetImage|contains:
        - '\AppData\Local\'
        - 'C:\Program Files (x86)\'
        - 'C:\Program Files\'
        - 'C:\Windows\Microsoft.NET\Framework64\'
filter_main_msiexec_2:
    SourceImage|endswith: '\msiexec.exe'
    TargetImage:
        - 'C:\Windows\System32\msiexec.exe'
        - 'C:\Windows\SysWOW64\msiexec.exe'
filter_main_iexplore:
    SourceImage: 'C:\Program Files\Internet Explorer\iexplore.exe'
    TargetImage:
        - 'C:\Program Files (x86)\Internet Explorer\iexplore.exe'
        - 'C:\Windows\System32\rundll32.exe'
filter_main_powerpnt:
    SourceImage|endswith: '\POWERPNT.EXE'
    TargetImage|contains:
        - 'C:\Program Files\Microsoft Office\'
        - 'C:\Program Files (x86)\Microsoft Office\'
filter_main_null:
    TargetImage: null
filter_main_empty:
    TargetImage: ''

Stage 3: not filter_optional_*

filter_optional_aurora_smartconsole1:
    SourceImage: 'C:\Program Files\internet explorer\iexplore.exe'
    SourceCommandLine|contains|all:
        - 'https://'
        - '.checkpoint.com/documents/'
        - 'SmartConsole_OLH/'
        - 'default.htm#cshid='
filter_optional_aurora_smartconsole2:
    SourceImage: 'C:\Program Files\internet explorer\iexplore.exe'
    SourceParentImage|startswith:
        - 'C:\Program Files\'
        - 'C:\Program Files (x86)\'
    SourceParentImage|contains|all:
        - '\CheckPoint\SmartConsole\'
        - '\SmartConsole.exe'
filter_optional_powerpnt:
    SourceImage|contains: '\Microsoft Office\'
    SourceImage|endswith: '\POWERPNT.EXE'
    TargetImage: 'C:\Windows\System32\csrss.exe'
filter_optional_onedrive:
    SourceImage: 'C:\Windows\explorer.exe'
    TargetImage|endswith: '\AppData\Local\Microsoft\OneDrive\OneDrive.exe'
filter_optional_aurora:
    SourceImage: 'C:\Windows\explorer.exe'
    TargetImage|endswith: '\aurora-dashboard.exe'
filter_optional_officesetup:
    SourceImage: 'C:\Windows\explorer.exe'
    TargetImage|endswith: '\OfficeSetup.exe'

Exclusions

Top-level NOT(...) conjuncts: predicates this rule actively suppresses.

FieldKindExcluded values
SourceImageeqC:\Windows\SysWOW64\schtasks.exe
SourceImageeqC:\Windows\System32\schtasks.exe
TargetImageeqC:\Windows\System32\conhost.exe
TargetImageeqC:\Program Files (x86)\Internet Explorer\iexplore.exe
TargetImageeqC:\Windows\System32\rundll32.exe
SourceImageeqC:\Program Files\Internet Explorer\iexplore.exe
TargetImageeqC:\Windows\SysWOW64\msiexec.exe
TargetImageeqC:\Windows\System32\msiexec.exe
SourceImageends_with\msiexec.exe
TargetImageeqC:\Windows\System32\AtBroker.exe
TargetImageeqC:\Windows\System32\LogonUI.exe
TargetImageeqC:\Windows\System32\csrss.exe
TargetImageeqC:\Windows\System32\dwm.exe
TargetImageeqC:\Windows\System32\fontdrvhost.exe
TargetImageeqC:\Windows\System32\services.exe
TargetImageeqC:\Windows\System32\userinit.exe
TargetImageeqC:\Windows\System32\wininit.exe
TargetImageeqC:\Windows\System32\wlrmdr.exe
SourceImageeqC:\Windows\System32\winlogon.exe
TargetImagematchC:\Program Files (x86)\
TargetImagematchC:\Program Files\
TargetImagematchC:\Windows\Microsoft.NET\Framework64\
TargetImagematch\AppData\Local\
SourceImageends_with\msiexec.exe
TargetImagematchC:\Program Files (x86)\Microsoft Office\
TargetImagematchC:\Program Files\Microsoft Office\
SourceImageends_with\POWERPNT.EXE
TargetImagestarts_withC:\Program Files (x86)\
TargetImagestarts_withC:\Program Files\
TargetImagestarts_withC:\Windows\SysWOW64\
TargetImagestarts_withC:\Windows\System32\
SourceImageeqC:\Windows\explorer.exe
SourceImageeqC:\Windows\System32\winlogon.exe
TargetParentProcessIdeq4
TargetImageeqSystem
TargetImageis_null(no value, null check)
SourceParentImagestarts_withC:\Program Files (x86)\
SourceParentImagestarts_withC:\Program Files\
SourceImageeqC:\Program Files\internet explorer\iexplore.exe
SourceParentImagematch\CheckPoint\SmartConsole\
SourceParentImagematch\SmartConsole.exe
SourceCommandLinematch.checkpoint.com/documents/
SourceCommandLinematchSmartConsole_OLH/
SourceCommandLinematchdefault.htm#cshid=
SourceCommandLinematchhttps://
SourceImageeqC:\Program Files\internet explorer\iexplore.exe
SourceImageends_with\POWERPNT.EXE
SourceImagematch\Microsoft Office\
TargetImageeqC:\Windows\System32\csrss.exe
SourceImageeqC:\Windows\explorer.exe
TargetImageends_with\AppData\Local\Microsoft\OneDrive\OneDrive.exe
SourceImageeqC:\Windows\explorer.exe
TargetImageends_with\OfficeSetup.exe
SourceImageeqC:\Windows\explorer.exe
TargetImageends_with\aurora-dashboard.exe

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
SourceImageends_with
  • \explorer.exe corpus 14 (sigma 14)
  • \iexplore.exe corpus 5 (sigma 5)
  • \msiexec.exe corpus 21 (sigma 21)
  • \powerpnt.exe corpus 15 (sigma 15)
  • \schtasks.exe corpus 56 (sigma 56)
  • \winlogon.exe corpus 6 (sigma 6)