Detection rules › Sigma

Sigma rules: 3g

RuleSeverity
Adwind RAT / JRAThigh
Azure Device or Configuration Modified or Deletedmedium
Azure Network Security Configuration Modified or Deletedmedium
Brutforce on Windows OpenSSH server with valid usershigh
Creation of an Executable by an Executablelow
Data Compressedlow
DD File Overwritelow
DLL Load via LSASShigh
DNS Query To Ufile.io - DNS Clientlow
Google Cloud Kubernetes Secrets Modified or Deletedmedium
Hijack Legit RDP Session to Move Laterallyhigh
Import PowerShell Modules From Suspicious Directories - ProcCreationmedium
Invoke-Obfuscation STDIN+ Launcher - Securityhigh
macOS SSH Connection Detectionmedium
Microsoft 365 - Impossible Travel Activitymedium
Mstsc.EXE Execution From Uncommon Parenthigh
Multifactor Authentication Deniedmedium
Netsh helper DLL abuse (process)high
New Kubernetes Service Account Createdlow
Okta New Admin Console Behaviourshigh
Potential CVE-2023-27363 Exploitation - HTA File Creation By FoxitPDFReaderhigh
Potential CVE-2026-33829 Exploitation - Windows Snipping Tool Remote File Path URIhigh
Potential Fake Instance Of Hxtsr.EXE Executedmedium
Potential RDP Tunneling Via Plinkhigh
PowerShell Get-Clipboard Cmdlet Via CLImedium
Powershell Sensitive File Discoverymedium
RDP shadow session started (command)high
Remote Access Tool - AnyDesk Incoming Connectionmedium
Ruby on Rails Framework Exceptionsmedium
Screen Capture - macOSlow
Steganography Extract Files with Steghidelow
Suspicious Non-Browser Network Communication With Google APImedium
Troubleshooting Pack Cmdlet Executionmedium
VBScript Payload Stored in Registryhigh
Webshell ReGeorg Detection Via Web Logshigh
Winget Admin Settings Modificationlow

Adwind RAT / JRAT

#
Status
test
Severity
high
Author
Florian Roth (Nextron Systems), Tom Ueltschi, Jonhnathan Ribeiro, oscd.community
Source
github.com/SigmaHQ/sigma

Detects javaw.exe in AppData folder as used by Adwind / JRAT

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Adwind RAT / JRAT
id: 1fac1481-2dbc-48b2-9096-753c49b4ec71
status: test
description: Detects javaw.exe in AppData folder as used by Adwind / JRAT
references:
    - https://www.hybrid-analysis.com/sample/ba86fa0d4b6af2db0656a88b1dd29f36fe362473ae8ad04255c4e52f214a541c?environmentId=100
    - https://www.first.org/resources/papers/conf2017/Advanced-Incident-Detection-and-Threat-Hunting-using-Sysmon-and-Splunk.pdf
author: Florian Roth (Nextron Systems), Tom Ueltschi, Jonhnathan Ribeiro, oscd.community
date: 2017-11-10
modified: 2022-10-09
tags:
    - attack.execution
    - attack.t1059.005
    - attack.t1059.007
    - detection.emerging-threats
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - CommandLine|contains|all:
              - '\AppData\Roaming\Oracle'
              - '\java'
              - '.exe '
        - CommandLine|contains|all:
              - 'cscript.exe'
              - 'Retrive'
              - '.vbs '
    condition: selection
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    - CommandLine|contains|all:
          - '\AppData\Roaming\Oracle'
          - '\java'
          - '.exe '
    - CommandLine|contains|all:
          - 'cscript.exe'
          - 'Retrive'
          - '.vbs '

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • .exe corpus 2 (sigma 2)
  • .vbs corpus 2 (sigma 2)
  • Retrive
  • \AppData\Roaming\Oracle
  • \java
  • cscript.exe
field:"CommandLine" kind:match

Azure Device or Configuration Modified or Deleted

#
Status
test
Severity
medium
Author
Austin Songer @austinsonger
Source
github.com/SigmaHQ/sigma

Identifies when a device or device configuration in azure is modified or deleted.

Known False Positives

  • Device or device configuration being modified or deleted may be performed by a system administrator.
  • Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
  • Device or device configuration modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.

MITRE ATT&CK Coverage

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: Azure Device or Configuration Modified or Deleted
id: 46530378-f9db-4af9-a9e5-889c177d3881
status: test
description: Identifies when a device or device configuration in azure is modified or deleted.
references:
    - https://learn.microsoft.com/en-us/entra/identity/monitoring-health/reference-audit-activities#core-directory
author: Austin Songer @austinsonger
date: 2021-09-03
modified: 2022-10-09
tags:
    - attack.impact
    - attack.t1485
    - attack.t1565.001
logsource:
    product: azure
    service: activitylogs
detection:
    selection:
        properties.message:
            - Delete device
            - Delete device configuration
            - Update device
            - Update device configuration
    condition: selection
falsepositives:
    - Device or device configuration being modified or deleted may be performed by a system administrator.
    - Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
    - Device or device configuration modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    properties.message:
        - Delete device
        - Delete device configuration
        - Update device
        - Update device configuration

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
properties.messageeq
  • Delete device
  • Delete device configuration
  • Update device
  • Update device configuration
field:"properties.message" kind:eq

Azure Network Security Configuration Modified or Deleted

#
Status
test
Severity
medium
Author
Austin Songer @austinsonger
Source
github.com/SigmaHQ/sigma

Identifies when a network security configuration is modified or deleted.

Known False Positives

  • Network Security Configuration being modified or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
  • Network Security Configuration modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.

MITRE ATT&CK Coverage

TacticTechniques
ImpactNo specific technique

Telemetry Coverage

Rule Body

title: Azure Network Security Configuration Modified or Deleted
id: d22b4df4-5a67-4859-a578-8c9a0b5af9df
status: test
description: Identifies when a network security configuration is modified or deleted.
references:
    - https://learn.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations
author: Austin Songer @austinsonger
date: 2021-08-08
modified: 2022-08-23
tags:
    - attack.impact
logsource:
    product: azure
    service: activitylogs
detection:
    selection:
        operationName:
            - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/WRITE
            - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/DELETE
            - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/SECURITYRULES/WRITE
            - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/SECURITYRULES/DELETE
            - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/JOIN/ACTION
            - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/PROVIDERS/MICROSOFT.INSIGHTS/DIAGNOSTICSETTINGS/WRITE
    condition: selection
falsepositives:
    - Network Security Configuration being modified or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
    - Network Security Configuration modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    operationName:
        - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/WRITE
        - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/DELETE
        - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/SECURITYRULES/WRITE
        - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/SECURITYRULES/DELETE
        - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/JOIN/ACTION
        - MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/PROVIDERS/MICROSOFT.INSIGHTS/DIAGNOSTICSETTINGS/WRITE

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
operationNameeq
  • MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/DELETE
  • MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/JOIN/ACTION
  • MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/PROVIDERS/MICROSOFT.INSIGHTS/DIAGNOSTICSETTINGS/WRITE
  • MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/SECURITYRULES/DELETE
  • MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/SECURITYRULES/WRITE corpus 2 (sigma 2)
  • MICROSOFT.NETWORK/NETWORKSECURITYGROUPS/WRITE
field:"operationName" kind:eq

Brutforce on Windows OpenSSH server with valid users

#
Status
experimental
Severity
high
Time window
30m
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker attempts to SSH brutforce a Windows OpenSSH server with a valid user.

Known False Positives

  • None

MITRE ATT&CK Coverage

TacticTechniques
Credential Access

Telemetry Coverage

Rule Body

title: Brutforce on Windows OpenSSH server with valid users
name: bruteforce_openssh_vaild_users
description: Detects scenarios where an attacker attempts to SSH brutforce a Windows OpenSSH server with a valid user.
remarks: This requires to have previously enabled the builtin OpenSSH server or to have installed the "OpenSSH-Win64" component. IpAddress or Workstation fields may be empty. In case Workstation field is not empty, be aware that it may wrongly report the source host. Also note that SSH logins are reported with logon type 8 (clear text). For reliable source IP information, use the logs from the OpenSSH channel, event ID 4.
references:
  - https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0006-Credential%20Access/T1110.xxx-Brut%20force
  - https://winaero.com/enable-openssh-server-windows-10/
  - https://docs.microsoft.com/en-us/windows-server/administration/openssh/openssh_install_firstuse
  - https://virtualizationreview.com/articles/2020/05/21/ssh-server-on-windows-10.aspx
tags:
  - attack.credential_access
  - attack.t1110
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 4625
    SubStatus: "0xc000006A" # invalid password | Failure code can be defined in "Status" or "Substatus" fields. Usually, if Substatus == 0x0, refers to Status.
    ProcessName|endswith: # Can be "C:\Program Files\OpenSSH-Win64\sshd.exe" or "C:\Windows\system32\OpenSSH\sshd.exe"
      - '\sshd.exe'
      - '\ssh.exe'
  condition: selection
falsepositives:
  - None
level: high

---
title: Brutforce on Windows OpenSSH server with valid users Count
status: experimental
correlation:
  type: value_count
  rules:
    - bruteforce_openssh_vaild_users # Referenced here
  group-by:
    - Computer
  timespan: 30m
  condition:
    gte: 20
    field: EventRecordID
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  EventID: 4625
  SubStatus: "0xc000006A"
  ProcessName|endswith:
    - '\sshd.exe'
    - '\ssh.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
ProcessNameends_with
  • \ssh.exe
  • \sshd.exe corpus 3 (sigma 3)
field:"process_name" kind:ends_with
SubStatuseq
  • 0xc000006A
field:"SubStatus" kind:eq value:"0xc000006A"

Creation of an Executable by an Executable

#
Status
test
Severity
low
Author
frack113
Source
github.com/SigmaHQ/sigma

Detects the creation of an executable by another executable.

Known False Positives

  • Software installers
  • Update utilities
  • 32bit applications launching their 64bit versions

MITRE ATT&CK Coverage

TacticTechniques
Resource Development

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Creation of an Executable by an Executable
id: 297afac9-5d02-4138-8c58-b977bac60556
status: test
description: Detects the creation of an executable by another executable.
references:
    - Internal Research
author: frack113
date: 2022-03-09
modified: 2025-02-24
tags:
    - attack.resource-development
    - attack.t1587.001
    - detection.threat-hunting
logsource:
    product: windows
    category: file_event
detection:
    selection:
        Image|endswith: '.exe'
        TargetFilename|endswith: '.exe'
    filter_main_generic_1:
        Image|endswith:
            - ':\Windows\System32\msiexec.exe'
            - ':\Windows\system32\cleanmgr.exe'
            - ':\Windows\explorer.exe'
            - ':\WINDOWS\system32\dxgiadaptercache.exe'
            - ':\WINDOWS\system32\Dism.exe'
            - ':\Windows\System32\wuauclt.exe'
    filter_main_update:
        # Security_UserID: S-1-5-18
        # Example:
        #   TargetFilename: C:\Windows\SoftwareDistribution\Download\803d1df4c931df4f3e50a022cda56e88\WindowsUpdateBox.exe
        Image|endswith: ':\WINDOWS\system32\svchost.exe'
        TargetFilename|contains: ':\Windows\SoftwareDistribution\Download\'
    filter_main_upgrade:
        Image|endswith: ':\Windows\system32\svchost.exe'
        TargetFilename|contains|all:
            # Example:
            #   This example was seen during windows upgrade
            #   TargetFilename: :\WUDownloadCache\803d1df4c931df4f3e50a022cda56e29\WindowsUpdateBox.exe
            - ':\WUDownloadCache\'
            - '\WindowsUpdateBox.exe'
    filter_main_windows_update_box:
        # This FP was seen during Windows Upgrade
        # ParentCommandLine: C:\WINDOWS\system32\svchost.exe -k netsvcs -p -s wuauserv
        Image|contains: ':\WINDOWS\SoftwareDistribution\Download\'
        Image|endswith: '\WindowsUpdateBox.Exe'
        TargetFilename|contains: ':\$WINDOWS.~BT\Sources\'
    filter_main_tiworker:
        Image|contains: ':\Windows\WinSxS\'
        Image|endswith: '\TiWorker.exe'
    filter_main_programfiles:
        - Image|contains:
              - ':\Program Files\'
              - ':\Program Files (x86)\'
        - TargetFilename|contains:
              - ':\Program Files\'
              - ':\Program Files (x86)\'
    filter_main_defender:
        Image|contains:
            - ':\ProgramData\Microsoft\Windows Defender\'
            - ':\Program Files\Windows Defender\'
    filter_main_windows_apps:
        TargetFilename|contains: '\AppData\Local\Microsoft\WindowsApps\'
    filter_main_teams:
        Image|endswith: '\AppData\Local\Microsoft\Teams\Update.exe'
        TargetFilename|endswith:
            - '\AppData\Local\Microsoft\Teams\stage\Teams.exe'
            - '\AppData\Local\Microsoft\Teams\stage\Squirrel.exe'
            - '\AppData\Local\Microsoft\SquirrelTemp\tempb\'
    filter_main_mscorsvw:
        # Example:
        #   ParentCommandLine: "C:\Windows\Microsoft.NET\Framework\v4.0.30319\ngen.exe" ExecuteQueuedItems /LegacyServiceBehavior
        #   Image: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\mscorsvw.exe
        #       TargetFilename: C:\Windows\assembly\NativeImages_v4.0.30319_32\Temp\4f8c-0\MSBuild.exe
        #       TargetFilename: C:\Windows\assembly\NativeImages_v4.0.30319_32\Temp\49bc-0\testhost.net47.x86.exe
        #       TargetFilename: C:\Windows\assembly\NativeImages_v4.0.30319_32\Temp\39d8-0\fsc.exe
        Image|contains:
            - ':\Windows\Microsoft.NET\Framework\'
            - ':\Windows\Microsoft.NET\Framework64\'
            - ':\Windows\Microsoft.NET\FrameworkArm\'
            - ':\Windows\Microsoft.NET\FrameworkArm64\'
        Image|endswith: '\mscorsvw.exe'
        TargetFilename|contains: ':\Windows\assembly\NativeImages_'
    filter_main_vscode:
        Image|contains: '\AppData\Local\'
        Image|endswith: '\Microsoft VS Code\Code.exe'
        TargetFilename|contains: '\.vscode\extensions\'
    filter_main_githubdesktop:
        Image|endswith: '\AppData\Local\GitHubDesktop\Update.exe'
        # Example TargetFileName:
        #   \AppData\Local\SquirrelTemp\tempb\lib\net45\GitHubDesktop_ExecutionStub.exe
        #   \AppData\Local\SquirrelTemp\tempb\lib\net45\squirrel.exe
        TargetFilename|contains: '\AppData\Local\SquirrelTemp\'
    filter_main_windows_temp:
        - Image|contains: ':\WINDOWS\TEMP\'
        - TargetFilename|contains: ':\WINDOWS\TEMP\'
    filter_optional_python:
        Image|contains: '\Python27\python.exe'
        TargetFilename|contains:
            - '\Python27\Lib\site-packages\'
            - '\Python27\Scripts\'
            - '\AppData\Local\Temp\'
    filter_optional_squirrel:
        Image|contains: '\AppData\Local\SquirrelTemp\Update.exe'
        TargetFilename|contains: '\AppData\Local'
    filter_main_temp_installers:
        - Image|contains: '\AppData\Local\Temp\'
        - TargetFilename|contains: '\AppData\Local\Temp\'
    filter_optional_chrome:
        Image|endswith: '\ChromeSetup.exe'
        TargetFilename|contains: '\Google'
    filter_main_dot_net:
        Image|contains: ':\Windows\Microsoft.NET\Framework'
        Image|endswith: '\mscorsvw.exe'
        TargetFilename|contains: ':\Windows\assembly'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    # Please contribute to FP to increase the level
    - Software installers
    - Update utilities
    - 32bit applications launching their 64bit versions
level: low

Stages and Predicates

Stage 0: condition

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

Stage 1: selection

selection:
    Image|endswith: '.exe'
    TargetFilename|endswith: '.exe'

Stage 2: not filter_main_*

filter_main_generic_1:
    Image|endswith:
        - ':\Windows\System32\msiexec.exe'
        - ':\Windows\system32\cleanmgr.exe'
        - ':\Windows\explorer.exe'
        - ':\WINDOWS\system32\dxgiadaptercache.exe'
        - ':\WINDOWS\system32\Dism.exe'
        - ':\Windows\System32\wuauclt.exe'
filter_main_update:
    Image|endswith: ':\WINDOWS\system32\svchost.exe'
    TargetFilename|contains: ':\Windows\SoftwareDistribution\Download\'
filter_main_upgrade:
    Image|endswith: ':\Windows\system32\svchost.exe'
    TargetFilename|contains|all:
        - ':\WUDownloadCache\'
        - '\WindowsUpdateBox.exe'
filter_main_windows_update_box:
    Image|contains: ':\WINDOWS\SoftwareDistribution\Download\'
    Image|endswith: '\WindowsUpdateBox.Exe'
    TargetFilename|contains: ':\$WINDOWS.~BT\Sources\'
filter_main_tiworker:
    Image|contains: ':\Windows\WinSxS\'
    Image|endswith: '\TiWorker.exe'
filter_main_programfiles:
    - Image|contains:
          - ':\Program Files\'
          - ':\Program Files (x86)\'
    - TargetFilename|contains:
          - ':\Program Files\'
          - ':\Program Files (x86)\'
filter_main_defender:
    Image|contains:
        - ':\ProgramData\Microsoft\Windows Defender\'
        - ':\Program Files\Windows Defender\'
filter_main_windows_apps:
    TargetFilename|contains: '\AppData\Local\Microsoft\WindowsApps\'
filter_main_teams:
    Image|endswith: '\AppData\Local\Microsoft\Teams\Update.exe'
    TargetFilename|endswith:
        - '\AppData\Local\Microsoft\Teams\stage\Teams.exe'
        - '\AppData\Local\Microsoft\Teams\stage\Squirrel.exe'
        - '\AppData\Local\Microsoft\SquirrelTemp\tempb\'
filter_main_mscorsvw:
    Image|contains:
        - ':\Windows\Microsoft.NET\Framework\'
        - ':\Windows\Microsoft.NET\Framework64\'
        - ':\Windows\Microsoft.NET\FrameworkArm\'
        - ':\Windows\Microsoft.NET\FrameworkArm64\'
    Image|endswith: '\mscorsvw.exe'
    TargetFilename|contains: ':\Windows\assembly\NativeImages_'
filter_main_vscode:
    Image|contains: '\AppData\Local\'
    Image|endswith: '\Microsoft VS Code\Code.exe'
    TargetFilename|contains: '\.vscode\extensions\'
filter_main_githubdesktop:
    Image|endswith: '\AppData\Local\GitHubDesktop\Update.exe'
    TargetFilename|contains: '\AppData\Local\SquirrelTemp\'
filter_main_windows_temp:
    - Image|contains: ':\WINDOWS\TEMP\'
    - TargetFilename|contains: ':\WINDOWS\TEMP\'
filter_main_temp_installers:
    - Image|contains: '\AppData\Local\Temp\'
    - TargetFilename|contains: '\AppData\Local\Temp\'
filter_main_dot_net:
    Image|contains: ':\Windows\Microsoft.NET\Framework'
    Image|endswith: '\mscorsvw.exe'
    TargetFilename|contains: ':\Windows\assembly'

Stage 3: not filter_optional_*

filter_optional_python:
    Image|contains: '\Python27\python.exe'
    TargetFilename|contains:
        - '\Python27\Lib\site-packages\'
        - '\Python27\Scripts\'
        - '\AppData\Local\Temp\'
filter_optional_squirrel:
    Image|contains: '\AppData\Local\SquirrelTemp\Update.exe'
    TargetFilename|contains: '\AppData\Local'
filter_optional_chrome:
    Image|endswith: '\ChromeSetup.exe'
    TargetFilename|contains: '\Google'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • .exe corpus 4 (sigma 4)
field:"Image" kind:ends_with value:".exe"
TargetFilenameends_with
  • .exe corpus 21 (sigma 20, splunk 1)
field:"TargetFilename" kind:ends_with value:".exe"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imagematch:\Windows\Microsoft.NET\Framework64\excludes:Image field:"Image" value:":\Windows\Microsoft.NET\Framework64\"
Imagematch:\Windows\Microsoft.NET\FrameworkArm64\excludes:Image field:"Image" value:":\Windows\Microsoft.NET\FrameworkArm64\"
Imagematch:\Windows\Microsoft.NET\FrameworkArm\excludes:Image field:"Image" value:":\Windows\Microsoft.NET\FrameworkArm\"
Imagematch:\Windows\Microsoft.NET\Framework\excludes:Image field:"Image" value:":\Windows\Microsoft.NET\Framework\"
Imageends_with\mscorsvw.exeexcludes:Image field:"Image" value:"\mscorsvw.exe"
TargetFilenamematch:\Windows\assembly\NativeImages_excludes:TargetFilename field:"TargetFilename" value:":\Windows\assembly\NativeImages_"
TargetFilenameends_with\AppData\Local\Microsoft\SquirrelTemp\tempb\excludes:TargetFilename field:"TargetFilename" value:"\AppData\Local\Microsoft\SquirrelTemp\tempb\"
TargetFilenameends_with\AppData\Local\Microsoft\Teams\stage\Squirrel.exeexcludes:TargetFilename field:"TargetFilename" value:"\AppData\Local\Microsoft\Teams\stage\Squirrel.exe"
TargetFilenameends_with\AppData\Local\Microsoft\Teams\stage\Teams.exeexcludes:TargetFilename field:"TargetFilename" value:"\AppData\Local\Microsoft\Teams\stage\Teams.exe"
Imageends_with\AppData\Local\Microsoft\Teams\Update.exeexcludes:Image field:"Image" value:"\AppData\Local\Microsoft\Teams\Update.exe"
Imageends_with:\WINDOWS\system32\svchost.exeexcludes:Image field:"Image" value:":\WINDOWS\system32\svchost.exe"
TargetFilenamematch:\Windows\SoftwareDistribution\Download\excludes:TargetFilename field:"TargetFilename" value:":\Windows\SoftwareDistribution\Download\"
Imageends_with:\Windows\system32\svchost.exeexcludes:Image field:"Image" value:":\Windows\system32\svchost.exe"
TargetFilenamematch:\WUDownloadCache\excludes:TargetFilename field:"TargetFilename" value:":\WUDownloadCache\"
TargetFilenamematch\WindowsUpdateBox.exeexcludes:TargetFilename field:"TargetFilename" value:"\WindowsUpdateBox.exe"
Imageends_with\AppData\Local\GitHubDesktop\Update.exeexcludes:Image field:"Image" value:"\AppData\Local\GitHubDesktop\Update.exe"
TargetFilenamematch\AppData\Local\SquirrelTemp\excludes:TargetFilename field:"TargetFilename" value:"\AppData\Local\SquirrelTemp\"
Imageends_with\Microsoft VS Code\Code.exeexcludes:Image field:"Image" value:"\Microsoft VS Code\Code.exe"
Imagematch\AppData\Local\excludes:Image field:"Image" value:"\AppData\Local\"
TargetFilenamematch\.vscode\extensions\excludes:TargetFilename field:"TargetFilename" value:"\.vscode\extensions\"
Imageends_with\TiWorker.exeexcludes:Image field:"Image" value:"\TiWorker.exe"
Imagematch:\Windows\WinSxS\excludes:Image field:"Image" value:":\Windows\WinSxS\"
Imageends_with\WindowsUpdateBox.Exeexcludes:Image field:"Image" value:"\WindowsUpdateBox.Exe"
Imagematch:\WINDOWS\SoftwareDistribution\Download\excludes:Image field:"Image" value:":\WINDOWS\SoftwareDistribution\Download\"
TargetFilenamematch:\$WINDOWS.~BT\Sources\excludes:TargetFilename field:"TargetFilename" value:":\$WINDOWS.~BT\Sources\"
Imagematch:\Windows\Microsoft.NET\Frameworkexcludes:Image field:"Image" value:":\Windows\Microsoft.NET\Framework"
TargetFilenamematch:\Windows\assemblyexcludes:TargetFilename field:"TargetFilename" value:":\Windows\assembly"
Imageends_with:\WINDOWS\system32\Dism.exeexcludes:Image field:"Image" value:":\WINDOWS\system32\Dism.exe"
Imageends_with:\WINDOWS\system32\dxgiadaptercache.exeexcludes:Image field:"Image" value:":\WINDOWS\system32\dxgiadaptercache.exe"
Imageends_with:\Windows\System32\msiexec.exeexcludes:Image field:"Image" value:":\Windows\System32\msiexec.exe"
Imageends_with:\Windows\System32\wuauclt.exeexcludes:Image field:"Image" value:":\Windows\System32\wuauclt.exe"
Imageends_with:\Windows\explorer.exeexcludes:Image field:"Image" value:":\Windows\explorer.exe"
Imageends_with:\Windows\system32\cleanmgr.exeexcludes:Image field:"Image" value:":\Windows\system32\cleanmgr.exe"
Imagematch:\Program Files (x86)\excludes:Image field:"Image" value:":\Program Files (x86)\"
Imagematch:\Program Files\excludes:Image field:"Image" value:":\Program Files\"
Imagematch:\Program Files\Windows Defender\excludes:Image field:"Image" value:":\Program Files\Windows Defender\"
Imagematch:\ProgramData\Microsoft\Windows Defender\excludes:Image field:"Image" value:":\ProgramData\Microsoft\Windows Defender\"
Imagematch:\WINDOWS\TEMP\excludes:Image field:"Image" value:":\WINDOWS\TEMP\"
Imagematch\AppData\Local\Temp\excludes:Image field:"Image" value:"\AppData\Local\Temp\"
TargetFilenamematch:\Program Files (x86)\excludes:TargetFilename field:"TargetFilename" value:":\Program Files (x86)\"
TargetFilenamematch:\Program Files\excludes:TargetFilename field:"TargetFilename" value:":\Program Files\"
TargetFilenamematch:\WINDOWS\TEMP\excludes:TargetFilename field:"TargetFilename" value:":\WINDOWS\TEMP\"
TargetFilenamematch\AppData\Local\Microsoft\WindowsApps\excludes:TargetFilename field:"TargetFilename" value:"\AppData\Local\Microsoft\WindowsApps\"
TargetFilenamematch\AppData\Local\Temp\excludes:TargetFilename field:"TargetFilename" value:"\AppData\Local\Temp\"
TargetFilenamematch\Python27\Lib\site-packages\excludes:TargetFilename field:"TargetFilename" value:"\Python27\Lib\site-packages\"
TargetFilenamematch\Python27\Scripts\excludes:TargetFilename field:"TargetFilename" value:"\Python27\Scripts\"
Imagematch\Python27\python.exeexcludes:Image field:"Image" value:"\Python27\python.exe"
Imageends_with\ChromeSetup.exeexcludes:Image field:"Image" value:"\ChromeSetup.exe"
TargetFilenamematch\Googleexcludes:TargetFilename field:"TargetFilename" value:"\Google"
Imagematch\AppData\Local\SquirrelTemp\Update.exeexcludes:Image field:"Image" value:"\AppData\Local\SquirrelTemp\Update.exe"
TargetFilenamematch\AppData\Localexcludes:TargetFilename field:"TargetFilename" value:"\AppData\Local"

Data Compressed

#
Status
test
Severity
low
Author
Timur Zinniatullin, oscd.community
Source
github.com/SigmaHQ/sigma

An adversary may compress data (e.g., sensitive documents) that is collected prior to exfiltration in order to make it portable and minimize the amount of data sent over the network.

Known False Positives

  • Legitimate use of archiving tools by legitimate user.

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Data Compressed
id: a3b5e3e9-1b49-4119-8b8e-0344a01f21ee
status: test
description: An adversary may compress data (e.g., sensitive documents) that is collected prior to exfiltration in order to make it portable and minimize the amount of data sent over the network.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/a78b9ed805ab9ea2e422e1aa7741e9407d82d7b1/atomics/T1560.001/T1560.001.md
author: Timur Zinniatullin, oscd.community
date: 2019-10-21
modified: 2023-07-28
tags:
    - attack.exfiltration
    - attack.collection
    - attack.t1560.001
logsource:
    product: linux
    service: auditd
detection:
    selection1:
        type: 'execve'
        a0: 'zip'
    selection2:
        type: 'execve'
        a0: 'gzip'
        a1: '-k'
    selection3:
        type: 'execve'
        a0: 'tar'
        a1|contains: '-c'
    condition: 1 of selection*
falsepositives:
    - Legitimate use of archiving tools by legitimate user.
level: low

Stages and Predicates

Stage 0: condition

1 of selection*

Stage 1: selection1

selection1:
    type: 'execve'
    a0: 'zip'

Stage 2: selection2

selection2:
    type: 'execve'
    a0: 'gzip'
    a1: '-k'

Stage 3: selection3

selection3:
    type: 'execve'
    a0: 'tar'
    a1|contains: '-c'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
a0eq
  • gzip
  • tar
  • zip
field:"a0" kind:eq
a1eq
  • -k
field:"a1" kind:eq value:"-k"
a1match
  • -c
field:"a1" kind:match value:"-c"
typeeq
  • execve corpus 37 (sigma 31, splunk 6)
field:"type" kind:eq value:"execve"

DD File Overwrite

#
Status
test
Severity
low
Author
Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC
Source
github.com/SigmaHQ/sigma

Detects potential overwriting and deletion of a file using DD.

Known False Positives

  • Any user deleting files that way.

MITRE ATT&CK Coverage

TacticTechniques
Impact

Telemetry Coverage

PlatformRecord / event type
LinuxEvent ID 1: Process Create

Rule Body

title: DD File Overwrite
id: 2953194b-e33c-4859-b9e8-05948c167447
status: test
description: Detects potential overwriting and deletion of a file using DD.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1485/T1485.md#atomic-test-2---macoslinux---overwrite-file-with-dd
author: Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), MSTIC
date: 2021-10-15
modified: 2022-07-07
tags:
    - attack.impact
    - attack.t1485
logsource:
    product: linux
    category: process_creation
detection:
    selection1:
        Image:
            - '/bin/dd'
            - '/usr/bin/dd'
    selection2:
        CommandLine|contains: 'of='
    selection3:
        CommandLine|contains:
            - 'if=/dev/zero'
            - 'if=/dev/null'
    condition: all of selection*
falsepositives:
    - Any user deleting files that way.
level: low

Stages and Predicates

Stage 0: condition

all of selection*

Stage 1: selection1

selection1:
    Image:
        - '/bin/dd'
        - '/usr/bin/dd'

Stage 2: selection2

selection2:
    CommandLine|contains: 'of='

Stage 3: selection3

selection3:
    CommandLine|contains:
        - 'if=/dev/zero'
        - 'if=/dev/null'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • if=/dev/null
  • if=/dev/zero corpus 3 (sigma 3)
  • of= corpus 3 (sigma 2, splunk 1)
field:"CommandLine" kind:match
Imageeq
  • /bin/dd
  • /usr/bin/dd
field:"Image" kind:eq

DLL Load via LSASS

#
Status
test
Severity
high
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects a method to load DLL via LSASS process using an undocumented Registry key

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: DLL Load via LSASS
id: b3503044-60ce-4bf4-bbcb-e3db98788823
status: test
description: Detects a method to load DLL via LSASS process using an undocumented Registry key
references:
    - https://blog.xpnsec.com/exploring-mimikatz-part-1/
    - https://twitter.com/SBousseaden/status/1183745981189427200
author: Florian Roth (Nextron Systems)
date: 2019-10-16
modified: 2022-04-21
tags:
    - attack.privilege-escalation
    - attack.execution
    - attack.persistence
    - attack.t1547.008
logsource:
    category: registry_event
    product: windows
detection:
    selection:
        TargetObject|contains:
            - '\CurrentControlSet\Services\NTDS\DirectoryServiceExtPt'
            - '\CurrentControlSet\Services\NTDS\LsaDbExtPt'
    filter_domain_controller:
        Image: 'C:\Windows\system32\lsass.exe'
        Details:
            - '%%systemroot%%\system32\ntdsa.dll'
            - '%%systemroot%%\system32\lsadb.dll'
    condition: selection and not 1 of filter_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_*

Stage 1: selection

selection:
    TargetObject|contains:
        - '\CurrentControlSet\Services\NTDS\DirectoryServiceExtPt'
        - '\CurrentControlSet\Services\NTDS\LsaDbExtPt'

Stage 2: not filter_domain_controller

filter_domain_controller:
    Image: 'C:\Windows\system32\lsass.exe'
    Details:
        - '%%systemroot%%\system32\ntdsa.dll'
        - '%%systemroot%%\system32\lsadb.dll'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetObjectmatch
  • \CurrentControlSet\Services\NTDS\DirectoryServiceExtPt
  • \CurrentControlSet\Services\NTDS\LsaDbExtPt
field:"TargetObject" kind:match

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Detailseq%%systemroot%%\system32\lsadb.dllexcludes:Details field:"Details" value:"%%systemroot%%\system32\lsadb.dll"
Detailseq%%systemroot%%\system32\ntdsa.dllexcludes:Details field:"Details" value:"%%systemroot%%\system32\ntdsa.dll"
ImageeqC:\Windows\system32\lsass.exeexcludes:Image field:"Image" value:"C:\Windows\system32\lsass.exe"

DNS Query To Ufile.io - DNS Client

#
Status
test
Severity
low
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects DNS queries to "ufile.io", which was seen abused by malware and threat actors as a method for data exfiltration

Known False Positives

  • DNS queries for "ufile" are not malicious by nature necessarily. Investigate the source to determine the necessary actions to take

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: DNS Query To Ufile.io - DNS Client
id: 090ffaad-c01a-4879-850c-6d57da98452d
related:
    - id: 1cbbeaaf-3c8c-4e4c-9d72-49485b6a176b
      type: similar
status: test
description: Detects DNS queries to "ufile.io", which was seen abused by malware and threat actors as a method for data exfiltration
references:
    - https://thedfirreport.com/2021/12/13/diavol-ransomware/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-01-16
modified: 2023-09-18
tags:
    - attack.exfiltration
    - attack.t1567.002
logsource:
    product: windows
    service: dns-client
    definition: 'Requirements: Microsoft-Windows-DNS Client Events/Operational Event Log must be enabled/collected in order to receive the events.'
detection:
    selection:
        EventID: 3008
        QueryName|contains: 'ufile.io'
    condition: selection
falsepositives:
    - DNS queries for "ufile" are not malicious by nature necessarily. Investigate the source to determine the necessary actions to take
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    EventID: 3008
    QueryName|contains: 'ufile.io'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
QueryNamematch
  • ufile.io corpus 2 (sigma 2)
field:"QueryName" kind:match value:"ufile.io"

Google Cloud Kubernetes Secrets Modified or Deleted

#
Status
test
Severity
medium
Author
Austin Songer @austinsonger
Source
github.com/SigmaHQ/sigma

Identifies when the Secrets are Modified or Deleted.

Known False Positives

  • Secrets being modified or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
  • Secrets modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.

MITRE ATT&CK Coverage

TacticTechniques
Credential AccessNo specific technique

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: Google Cloud Kubernetes Secrets Modified or Deleted
id: 2f0bae2d-bf20-4465-be86-1311addebaa3
status: test
description: Identifies when the Secrets are Modified or Deleted.
references:
    - https://cloud.google.com/kubernetes-engine/docs/how-to/audit-logging
author: Austin Songer @austinsonger
date: 2021-08-09
modified: 2022-10-09
tags:
    - attack.credential-access
logsource:
    product: gcp
    service: gcp.audit
detection:
    selection:
        gcp.audit.method_name:
            - io.k8s.core.v*.secrets.create
            - io.k8s.core.v*.secrets.update
            - io.k8s.core.v*.secrets.patch
            - io.k8s.core.v*.secrets.delete
    condition: selection
falsepositives:
    - Secrets being modified or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
    - Secrets modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    gcp.audit.method_name:
        - io.k8s.core.v*.secrets.create
        - io.k8s.core.v*.secrets.update
        - io.k8s.core.v*.secrets.patch
        - io.k8s.core.v*.secrets.delete

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
gcp.audit.method_namewildcard
  • io.k8s.core.v*.secrets.create
  • io.k8s.core.v*.secrets.delete
  • io.k8s.core.v*.secrets.patch
  • io.k8s.core.v*.secrets.update
field:"gcp::method_name" kind:wildcard

Hijack Legit RDP Session to Move Laterally

#
Status
test
Severity
high
Author
Samir Bousseaden
Source
github.com/SigmaHQ/sigma

Detects the usage of tsclient share to place a backdoor on the RDP source machine's startup folder

Known False Positives

  • Unlikely

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Hijack Legit RDP Session to Move Laterally
id: 52753ea4-b3a0-4365-910d-36cff487b789
status: test
description: Detects the usage of tsclient share to place a backdoor on the RDP source machine's startup folder
author: Samir Bousseaden
references:
    - Internal Research
date: 2019-02-21
modified: 2021-11-27
tags:
    - attack.command-and-control
    - attack.t1219.002
logsource:
    product: windows
    category: file_event
detection:
    selection:
        Image|endswith: '\mstsc.exe'
        TargetFilename|contains: '\Microsoft\Windows\Start Menu\Programs\Startup\'
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\mstsc.exe'
    TargetFilename|contains: '\Microsoft\Windows\Start Menu\Programs\Startup\'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \mstsc.exe corpus 6 (sigma 6)
field:"Image" kind:ends_with value:"\mstsc.exe"
TargetFilenamematch
  • \Microsoft\Windows\Start Menu\Programs\Startup\ corpus 3 (sigma 2, splunk 1)
field:"TargetFilename" kind:match value:"\Microsoft\Windows\Start Menu\Programs\Startup\"

Import PowerShell Modules From Suspicious Directories - ProcCreation

#
Status
test
Severity
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects powershell scripts that import modules from suspicious directories

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Import PowerShell Modules From Suspicious Directories - ProcCreation
id: c31364f7-8be6-4b77-8483-dd2b5a7b69a3
related:
    - id: 21f9162c-5f5d-4b01-89a8-b705bd7d10ab
      type: similar
status: test
description: Detects powershell scripts that import modules from suspicious directories
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1003.002/T1003.002.md
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-01-10
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains:
            - 'Import-Module "$Env:Temp\'
            - Import-Module '$Env:Temp\
            - 'Import-Module $Env:Temp\'
            - 'Import-Module "$Env:Appdata\'
            - Import-Module '$Env:Appdata\
            - 'Import-Module $Env:Appdata\'
            - 'Import-Module C:\Users\Public\'
            # Import-Module alias is "ipmo"
            - 'ipmo "$Env:Temp\'
            - ipmo '$Env:Temp\
            - 'ipmo $Env:Temp\'
            - 'ipmo "$Env:Appdata\'
            - ipmo '$Env:Appdata\
            - 'ipmo $Env:Appdata\'
            - 'ipmo C:\Users\Public\'
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    CommandLine|contains:
        - 'Import-Module "$Env:Temp\'
        - Import-Module '$Env:Temp\
        - 'Import-Module $Env:Temp\'
        - 'Import-Module "$Env:Appdata\'
        - Import-Module '$Env:Appdata\
        - 'Import-Module $Env:Appdata\'
        - 'Import-Module C:\Users\Public\'
        - 'ipmo "$Env:Temp\'
        - ipmo '$Env:Temp\
        - 'ipmo $Env:Temp\'
        - 'ipmo "$Env:Appdata\'
        - ipmo '$Env:Appdata\
        - 'ipmo $Env:Appdata\'
        - 'ipmo C:\Users\Public\'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • Import-Module "$Env:Appdata\
  • Import-Module "$Env:Temp\
  • Import-Module $Env:Appdata\
  • Import-Module $Env:Temp\
  • Import-Module '$Env:Appdata\
  • Import-Module '$Env:Temp\
  • Import-Module C:\Users\Public\
  • ipmo "$Env:Appdata\
  • ipmo "$Env:Temp\
  • ipmo $Env:Appdata\
  • ipmo $Env:Temp\
  • ipmo '$Env:Appdata\
  • ipmo '$Env:Temp\
  • ipmo C:\Users\Public\
field:"CommandLine" kind:match

Invoke-Obfuscation STDIN+ Launcher - Security

#
Status
test
Severity
high
Author
Jonathan Cheong, oscd.community
Source
github.com/SigmaHQ/sigma

Detects Obfuscated use of stdin to execute PowerShell

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Invoke-Obfuscation STDIN+ Launcher - Security
id: 0c718a5e-4284-4fb9-b4d9-b9a50b3a1974
related:
    - id: 72862bf2-0eb1-11eb-adc1-0242ac120002
      type: derived
status: test
description: Detects Obfuscated use of stdin to execute PowerShell
references:
    - https://github.com/SigmaHQ/sigma/issues/1009  # (Task 25)
author: Jonathan Cheong, oscd.community
date: 2020-10-15
modified: 2022-11-29
tags:
    - attack.stealth
    - attack.t1027
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    service: security
    definition: The 'System Security Extension' audit subcategory need to be enabled to log the EID 4697
detection:
    selection:
        EventID: 4697
        ServiceFileName|contains|all:
            - 'cmd'
            - 'powershell'
    selection2:
        ServiceFileName|contains:
            - '${input}'
            - 'noexit'
    selection3:
        ServiceFileName|contains:
            - ' /c '
            - ' /r '
    condition: all of selection*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

all of selection*

Stage 1: selection

selection:
    EventID: 4697
    ServiceFileName|contains|all:
        - 'cmd'
        - 'powershell'

Stage 2: selection2

selection2:
    ServiceFileName|contains:
        - '${input}'
        - 'noexit'

Stage 3: selection3

selection3:
    ServiceFileName|contains:
        - ' /c '
        - ' /r '

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
ServiceFileNamematch
  • /c
  • /r
  • ${input}
  • cmd corpus 5 (sigma 5)
  • noexit
  • powershell corpus 4 (sigma 4)
field:"ServiceFileName" kind:match

macOS SSH Connection Detection

#
Status
experimental
Severity
medium
Author
Eric Brown - Nebulock, Inc.
Source
github.com/Nebulock-Inc/macos-coresigma

Detects execution of SSH client or SSH daemon processes which may indicate initial access attempts or remote connections. Monitor for unauthorized SSH connections, especially from unexpected users or to sensitive systems.

Known False Positives

  • Legitimate SSH usage by administrators
  • Automated scripts using SSH for remote management
  • CI/CD pipelines using SSH for deployments

MITRE ATT&CK Coverage

Rule Body

title: macOS SSH Connection Detection
id: a1b2c3d4-e5f6-4a7b-8c9d-0e1f2a3b4c5d
status: experimental
description: 'Detects execution of SSH client or SSH daemon processes which may indicate

  initial access attempts or remote connections. Monitor for unauthorized SSH

  connections, especially from unexpected users or to sensitive systems.

  '
author: Eric Brown - Nebulock, Inc.
date: 2025/10/31
modified: 2025/10/31
references:
- https://attack.mitre.org/techniques/T1078/004/
- https://attack.mitre.org/techniques/T1021/004/
logsource:
  product: macos
  service: endpointsecurity
detection:
  selection_event:
    esf.event_type: 9
    event.action: exec
  selection_process:
    Image|endswith:
    - /ssh
    - /sshd
  condition: selection_event and selection_process
falsepositives:
- Legitimate SSH usage by administrators
- Automated scripts using SSH for remote management
- CI/CD pipelines using SSH for deployments
fields:
- Image
- CommandLine
- ProcessId
- ParentProcessId
- User
tags:
- attack.initial_access
- attack.t1078.004
- attack.lateral_movement
- attack.t1021.004
level: medium

Stages and Predicates

Stage 0: condition

selection_event and selection_process

Stage 1: selection_event

selection_event:
  esf.event_type: 9
  event.action: exec

Stage 2: selection_process

selection_process:
  Image|endswith:
  - /ssh
  - /sshd

Indicators

These rows show field, operator, and value matches.

Microsoft 365 - Impossible Travel Activity

#
Status
test
Severity
medium
Author
Austin Songer @austinsonger
Source
github.com/SigmaHQ/sigma

Detects when a Microsoft Cloud App Security reported a risky sign-in attempt due to a login associated with an impossible travel.

MITRE ATT&CK Coverage

TacticTechniques
Initial Access
Persistence
Privilege Escalation
Stealth

Telemetry Coverage

PlatformRecord / event type
Microsoft 365Impossible travel activity

Rule Body

title: Microsoft 365 - Impossible Travel Activity
id: d7eab125-5f94-43df-8710-795b80fa1189
status: test
description: Detects when a Microsoft Cloud App Security reported a risky sign-in attempt due to a login associated with an impossible travel.
references:
    - https://learn.microsoft.com/en-us/defender-cloud-apps/anomaly-detection-policy
    - https://learn.microsoft.com/en-us/defender-cloud-apps/policy-template-reference
author: Austin Songer @austinsonger
date: 2020-07-06
modified: 2021-11-27
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.initial-access
    - attack.stealth
    - attack.t1078
logsource:
    service: threat_management
    product: m365
detection:
    selection:
        eventSource: SecurityComplianceCenter
        eventName: 'Impossible travel activity'
        status: success
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    eventSource: SecurityComplianceCenter
    eventName: 'Impossible travel activity'
    status: success

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
eventNameeq
  • Impossible travel activity
field:"aws::eventName" kind:eq value:"Impossible travel activity"
eventSourceeq
  • SecurityComplianceCenter corpus 14 (sigma 14)
field:"aws::eventSource" kind:eq value:"SecurityComplianceCenter"
statuseq
  • success corpus 21 (sigma 15, splunk 6)
field:"status" kind:eq value:"success"

Mstsc.EXE Execution From Uncommon Parent

#
Status
test
Severity
high
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects potential RDP connection via Mstsc using a local ".rdp" file located in suspicious locations.

Known False Positives

  • Unlikely

MITRE ATT&CK Coverage

TacticTechniques
Lateral MovementNo specific technique

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule Body

title: Mstsc.EXE Execution From Uncommon Parent
id: ff3b6b39-e765-42f9-bb2c-ea6761e0e0f6
status: test
description: Detects potential RDP connection via Mstsc using a local ".rdp" file located in suspicious locations.
references:
    - https://www.blackhillsinfosec.com/rogue-rdp-revisiting-initial-access-methods/
    - https://web.archive.org/web/20230726144748/https://blog.thickmints.dev/mintsights/detecting-rogue-rdp/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-04-18
tags:
    - attack.lateral-movement
logsource:
    category: process_creation
    product: windows
detection:
    selection_parent:
        ParentImage|endswith:
            # Covers potential downloads/clicks from browsers
            - '\brave.exe'
            - '\CCleanerBrowser.exe'
            - '\chrome.exe'
            - '\chromium.exe'
            - '\firefox.exe'
            - '\iexplore.exe'
            - '\microsoftedge.exe'
            - '\msedge.exe'
            - '\opera.exe'
            - '\vivaldi.exe'
            - '\whale.exe'
            # Covers potential downloads/clicks from email clients
            - '\outlook.exe'
    selection_img:
        - Image|endswith: '\mstsc.exe'
        - OriginalFileName: 'mstsc.exe'
    condition: all of selection_*
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_parent

selection_parent:
    ParentImage|endswith:
        - '\brave.exe'
        - '\CCleanerBrowser.exe'
        - '\chrome.exe'
        - '\chromium.exe'
        - '\firefox.exe'
        - '\iexplore.exe'
        - '\microsoftedge.exe'
        - '\msedge.exe'
        - '\opera.exe'
        - '\vivaldi.exe'
        - '\whale.exe'
        - '\outlook.exe'

Stage 2: selection_img

selection_img:
    - Image|endswith: '\mstsc.exe'
    - OriginalFileName: 'mstsc.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \mstsc.exe corpus 6 (sigma 6)
field:"Image" kind:ends_with value:"\mstsc.exe"
OriginalFileNameeq
  • mstsc.exe corpus 5 (sigma 4, elastic 1)
field:"OriginalFileName" kind:eq value:"mstsc.exe"
ParentImageends_with
  • \CCleanerBrowser.exe
  • \brave.exe corpus 2 (sigma 2)
  • \chrome.exe corpus 5 (sigma 5)
  • \chromium.exe
  • \firefox.exe corpus 4 (sigma 4)
  • \iexplore.exe corpus 2 (sigma 2)
  • \microsoftedge.exe corpus 2 (sigma 2)
  • \msedge.exe corpus 4 (sigma 4)
  • \opera.exe
  • \outlook.exe corpus 5 (sigma 5)
  • \vivaldi.exe corpus 2 (sigma 2)
  • \whale.exe
field:"ParentImage" kind:ends_with

Multifactor Authentication Denied

#
Status
test
Severity
medium
Author
AlertIQ
Source
github.com/SigmaHQ/sigma

User has indicated they haven't instigated the MFA prompt and could indicate an attacker has the password for the account.

Known False Positives

  • Users actually login but miss-click into the Deny button when MFA prompt.

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Multifactor Authentication Denied
id: e40f4962-b02b-4192-9bfe-245f7ece1f99
status: test
description: User has indicated they haven't instigated the MFA prompt and could indicate an attacker has the password for the account.
references:
    - https://www.microsoft.com/security/blog/2022/03/22/dev-0537-criminal-actor-targeting-organizations-for-data-exfiltration-and-destruction/
author: AlertIQ
date: 2022-03-24
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.initial-access
    - attack.credential-access
    - attack.stealth
    - attack.t1078.004
    - attack.t1110
    - attack.t1621
logsource:
    product: azure
    service: signinlogs
detection:
    selection:
        AuthenticationRequirement: 'multiFactorAuthentication'
        Status|contains: 'MFA Denied'
    condition: selection
falsepositives:
    - Users actually login but miss-click into the Deny button when MFA prompt.
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    AuthenticationRequirement: 'multiFactorAuthentication'
    Status|contains: 'MFA Denied'

Indicators

These rows show field, operator, and value matches.

Netsh helper DLL abuse (process)

#
Status
experimental
Severity
high
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker abuses the Netsh DLL feature to perform some code execution.

Known False Positives

  • Administrator activity

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Netsh helper DLL abuse (process)
description: Detects scenarios where an attacker abuses the Netsh DLL feature to perform some code execution. 
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0003-Persistence/T1546-Event%20Triggered%20Execution
- https://www.hackingarticles.in/windows-persistence-using-netsh/
- https://liberty-shell.com/sec/2018/07/28/netshlep/
- https://github.com/outflanknl/NetshHelperBeacon
- https://www.ired.team/offensive-security/persistence/t1128-netsh-helper-dll
- https://lolbas-project.github.io/lolbas/Binaries/Netsh/
- https://pentestlab.blog/2019/10/29/persistence-netsh-helper-dll/
tags:
- attack.persistence
- attack.t1546.007
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  category: process_creation
detection:
  selection:
    EventID: 4688
    NewProcessName|endswith: '\netsh.exe' # Full path "C:\Windows\system32\netsh.exe"
    Commandline|contains|all: # full command 'netsh add helper virus.dll'
      - netsh
      - add
      - helper
  condition: selection
falsepositives:
- Administrator activity
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  EventID: 4688
  NewProcessName|endswith: '\netsh.exe'
  Commandline|contains|all:
    - netsh
    - add
    - helper

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Commandlinematch
  • add corpus 30 (sigma 26, splunk 4)
  • helper corpus 2 (sigma 2)
  • netsh corpus 9 (sigma 9)
field:"CommandLine" kind:match
NewProcessNameends_with
  • \netsh.exe corpus 28 (sigma 28)
field:"Image" kind:ends_with value:"\netsh.exe"

New Kubernetes Service Account Created

#
Status
test
Severity
low
Author
Leo Tsaousis (@laripping)
Source
github.com/SigmaHQ/sigma

Detects creation of new Kubernetes service account, which could indicate an attacker's attempt to persist within a cluster.

MITRE ATT&CK Coverage

TacticTechniques
Persistence

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: New Kubernetes Service Account Created
id: e31bae15-83ed-473e-bf31-faf4f8a17d36
related:
    - id: 12d027c3-b48c-4d9d-8bb6-a732200034b2
      type: derived
status: test
description: |
    Detects creation of new Kubernetes service account, which could indicate an attacker's attempt to persist within a cluster.
references:
    - https://microsoft.github.io/Threat-Matrix-for-Kubernetes/techniques/container%20service%20account/
author: Leo Tsaousis (@laripping)
date: 2024-03-26
tags:
    - attack.persistence
    - attack.t1136
logsource:
    category: application
    product: kubernetes
    service: audit
detection:
    selection:
        verb: 'create'
        objectRef.resource: 'serviceaccounts'
    condition: selection
falsepositives:
    - Unknown
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    verb: 'create'
    objectRef.resource: 'serviceaccounts'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
objectRef.resourceeq
  • serviceaccounts
field:"objectRef.resource" kind:eq value:"serviceaccounts"
verbeq
  • create corpus 23 (sigma 10, splunk 7, panther 6)
field:"verb" kind:eq value:"create"

Okta New Admin Console Behaviours

#
Status
test
Severity
high
Author
kelnage
Source
github.com/SigmaHQ/sigma

Detects when Okta identifies new activity in the Admin Console.

Known False Positives

  • When an admin begins using the Admin Console and one of Okta's heuristics incorrectly identifies the behavior as being unusual.

MITRE ATT&CK Coverage

Telemetry Coverage

Rules Detecting the Same Action

These rules filter on the same operation.

Rule Body

title: Okta New Admin Console Behaviours
id: a0b38b70-3cb5-484b-a4eb-c4d8e7bcc0a9
status: test
description: Detects when Okta identifies new activity in the Admin Console.
references:
    - https://developer.okta.com/docs/reference/api/system-log/
    - https://sec.okta.com/articles/2023/08/cross-tenant-impersonation-prevention-and-detection
author: kelnage
date: 2023-09-07
modified: 2026-04-27
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.initial-access
    - attack.stealth
    - attack.t1078.004
logsource:
    product: okta
    service: okta
detection:
    selection_event:
        eventType: 'policy.evaluate_sign_on'
        target.displayName: 'Okta Admin Console'
    selection_positive:
        - debugContext.debugData.behaviors|contains: 'POSITIVE'
        - debugContext.debugData.logOnlySecurityData|contains: 'POSITIVE'
    condition: all of selection_*
falsepositives:
    - When an admin begins using the Admin Console and one of Okta's heuristics incorrectly identifies the behavior as being unusual.
level: high

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_event

selection_event:
    eventType: 'policy.evaluate_sign_on'
    target.displayName: 'Okta Admin Console'

Stage 2: selection_positive

selection_positive:
    - debugContext.debugData.behaviors|contains: 'POSITIVE'
    - debugContext.debugData.logOnlySecurityData|contains: 'POSITIVE'

Indicators

These rows show field, operator, and value matches.

Potential CVE-2023-27363 Exploitation - HTA File Creation By FoxitPDFReader

#
Status
test
Severity
high
Author
Gregory
Source
github.com/SigmaHQ/sigma

Detects suspicious ".hta" file creation in the startup folder by Foxit Reader. This can be an indication of CVE-2023-27363 exploitation.

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule Body

title: Potential CVE-2023-27363 Exploitation - HTA File Creation By FoxitPDFReader
id: 9cae055f-e1d2-4f81-b8a5-1986a68cdd84
status: test
description: Detects suspicious ".hta" file creation in the startup folder by Foxit Reader. This can be an indication of CVE-2023-27363 exploitation.
references:
    - https://github.com/j00sean/SecBugs/tree/ff72d553f75d93e1a0652830c0f74a71b3f19c46/CVEs/CVE-2023-27363
    - https://www.zerodayinitiative.com/advisories/ZDI-23-491/
    - https://www.tarlogic.com/blog/cve-2023-27363-foxit-reader/
author: Gregory
date: 2023-10-11
tags:
    - attack.persistence
    - attack.t1505.001
    - cve.2023-27363
    - detection.emerging-threats
logsource:
    product: windows
    category: file_event
detection:
    selection:
        Image|endswith: '\FoxitPDFReader.exe'
        TargetFilename|contains: '\Microsoft\Windows\Start Menu\Programs\Startup\'
        TargetFilename|endswith: '.hta'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\FoxitPDFReader.exe'
    TargetFilename|contains: '\Microsoft\Windows\Start Menu\Programs\Startup\'
    TargetFilename|endswith: '.hta'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \FoxitPDFReader.exe
field:"Image" kind:ends_with value:"\FoxitPDFReader.exe"
TargetFilenameends_with
  • .hta corpus 14 (sigma 14)
field:"TargetFilename" kind:ends_with value:".hta"
TargetFilenamematch
  • \Microsoft\Windows\Start Menu\Programs\Startup\ corpus 3 (sigma 2, splunk 1)
field:"TargetFilename" kind:match value:"\Microsoft\Windows\Start Menu\Programs\Startup\"

Potential CVE-2026-33829 Exploitation - Windows Snipping Tool Remote File Path URI

#
Status
test
Severity
high
Author
Samir Bousseaden, Swachchhanda Shrawan Poudel (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects potential exploitation of CVE-2026-33829, a vulnerability in the Windows Snipping Tool URI handler (ms-screensketch:). An attacker can abuse the 'filePath' parameter to supply a UNC path or HTTP URL, causing SnippingTool.exe to initiate a connection to a remote resource. When a UNC path is used (e.g. \attacker.com\share), this triggers an outbound NTLM authentication attempt, allowing the attacker to capture or relay the victim's Net-NTLMv2 hash. HTTP-based paths may result in remote file loading or server-side request forgery (SSRF)-style access. The URI can be delivered via a malicious hyperlink, phishing email, or web page.

MITRE ATT&CK Coverage

TacticTechniques
Credential Access

Telemetry Coverage

Rule Body

title: Potential CVE-2026-33829 Exploitation - Windows Snipping Tool Remote File Path URI
id: 7c3a5b1d-9e2f-4a8c-b5d7-1e0f3c6a9b2d
status: test
description: |
    Detects potential exploitation of CVE-2026-33829, a vulnerability in the Windows Snipping Tool URI handler (ms-screensketch:).
    An attacker can abuse the 'filePath' parameter to supply a UNC path or HTTP URL, causing SnippingTool.exe to initiate a connection to a remote resource.
    When a UNC path is used (e.g. \\attacker.com\share), this triggers an outbound NTLM authentication attempt, allowing the attacker to capture or relay the victim's Net-NTLMv2 hash.
    HTTP-based paths may result in remote file loading or server-side request forgery (SSRF)-style access.
    The URI can be delivered via a malicious hyperlink, phishing email, or web page.
references:
    - https://x.com/BlackArrowSec/status/2044374743491424508
    - https://x.com/SBousseaden/status/2044417029721997635
author: Samir Bousseaden, Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2026-04-28
tags:
    - attack.credential-access
    - attack.t1187
    - detection.emerging-threats
    - cve.2026-33829
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\SnippingTool.exe'
        CommandLine|contains:
            # '\\\\'  = literal double backslash (UNC path start); '%5C' and '%%5C' are URL-encoded variations of the same backslash character
            - 'ms-screensketch:edit?&filePath=\\\\'
            - 'ms-screensketch:edit?&filePath=%%5C'
            - 'ms-screensketch:edit?&filePath=%5C'
            - 'ms-screensketch:edit?&filePath=http'
    condition: selection
falsepositives:
    - Unknown
level: high
regression_tests_path: regression_data/rules-emerging-threats/2026/Exploits/CVE-2026-33829/proc_creation_win_exploit_cve_2026_33829/info.yml

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\SnippingTool.exe'
    CommandLine|contains:
        - 'ms-screensketch:edit?&filePath=\\\\'
        - 'ms-screensketch:edit?&filePath=%%5C'
        - 'ms-screensketch:edit?&filePath=%5C'
        - 'ms-screensketch:edit?&filePath=http'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • ms-screensketch:edit?&filePath=%%5C
  • ms-screensketch:edit?&filePath=%5C
  • ms-screensketch:edit?&filePath=\\\\
  • ms-screensketch:edit?&filePath=http
field:"CommandLine" kind:match
Imageends_with
  • \SnippingTool.exe
field:"Image" kind:ends_with value:"\SnippingTool.exe"

Potential Fake Instance Of Hxtsr.EXE Executed

#
Status
test
Severity
medium
Author
Sreeman
Source
github.com/SigmaHQ/sigma

HxTsr.exe is a Microsoft compressed executable file called Microsoft Outlook Communications. HxTsr.exe is part of Outlook apps, because it resides in a hidden "WindowsApps" subfolder of "C:\Program Files". Any instances of hxtsr.exe not in this folder may be malware camouflaging itself as HxTsr.exe

MITRE ATT&CK Coverage

TacticTechniques
Stealth

Telemetry Coverage

Rule Body

title: Potential Fake Instance Of Hxtsr.EXE Executed
id: 4e762605-34a8-406d-b72e-c1a089313320
status: test
description: |
    HxTsr.exe is a Microsoft compressed executable file called Microsoft Outlook Communications.
    HxTsr.exe is part of Outlook apps, because it resides in a hidden "WindowsApps" subfolder of "C:\Program Files".
    Any instances of hxtsr.exe not in this folder may be malware camouflaging itself as HxTsr.exe
references:
    - Internal Research
author: Sreeman
date: 2020-04-17
modified: 2024-02-08
tags:
    - attack.stealth
    - attack.t1036
logsource:
    product: windows
    category: process_creation
detection:
    # TODO: Link this to the more generic system process rule
    selection:
        Image|endswith: '\hxtsr.exe'
    filter_main_hxtsr:
        Image|contains: ':\program files\windowsapps\microsoft.windowscommunicationsapps_'
        Image|endswith: '\hxtsr.exe'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    Image|endswith: '\hxtsr.exe'

Stage 2: not filter_main_hxtsr

filter_main_hxtsr:
    Image|contains: ':\program files\windowsapps\microsoft.windowscommunicationsapps_'
    Image|endswith: '\hxtsr.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \hxtsr.exe
field:"Image" kind:ends_with value:"\hxtsr.exe"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imageends_with\hxtsr.exeexcludes:Image field:"Image" value:"\hxtsr.exe"
Imagematch:\program files\windowsapps\microsoft.windowscommunicationsapps_excludes:Image field:"Image" value:":\program files\windowsapps\microsoft.windowscommunicationsapps_"

Potential RDP Tunneling Via Plink

#

PowerShell Get-Clipboard Cmdlet Via CLI

#
Status
test
Severity
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects usage of the 'Get-Clipboard' cmdlet via CLI

MITRE ATT&CK Coverage

TacticTechniques
Collection

Telemetry Coverage

Rule Body

title: PowerShell Get-Clipboard Cmdlet Via CLI
id: b9aeac14-2ffd-4ad3-b967-1354a4e628c3
related:
    - id: 4cbd4f12-2e22-43e3-882f-bff3247ffb78
      type: derived
status: test
description: Detects usage of the 'Get-Clipboard' cmdlet via CLI
references:
    - https://github.com/OTRF/detection-hackathon-apt29/issues/16
    - https://github.com/OTRF/ThreatHunter-Playbook/blob/2d4257f630f4c9770f78d0c1df059f891ffc3fec/docs/evals/apt29/detections/3.B.2_C36B49B5-DF58-4A34-9FE9-56189B9DEFEA.md
author: Nasreddine Bencherchali (Nextron Systems)
date: 2020-05-02
modified: 2022-12-25
tags:
    - attack.collection
    - attack.t1115
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains: 'Get-Clipboard'
    condition: selection
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    CommandLine|contains: 'Get-Clipboard'

Indicators

These rows show field, operator, and value matches.

Powershell Sensitive File Discovery

#
Status
test
Severity
medium
Author
frack113
Source
github.com/SigmaHQ/sigma

Detect adversaries enumerate sensitive files

MITRE ATT&CK Coverage

TacticTechniques
Discovery

Telemetry Coverage

Rule Body

title: Powershell Sensitive File Discovery
id: 7d416556-6502-45b2-9bad-9d2f05f38997
related:
    - id: d23f2ba5-9da0-4463-8908-8ee47f614bb9
      type: derived
status: test
description: Detect adversaries enumerate sensitive files
references:
    - https://twitter.com/malmoeb/status/1570814999370801158
author: frack113
date: 2022-09-16
tags:
    - attack.discovery
    - attack.t1083
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection_action:
        ScriptBlockText|contains:
            - ls
            - get-childitem
            - gci
    selection_recurse:
        ScriptBlockText|contains: '-recurse'
    selection_file:
        ScriptBlockText|contains:
            - '.pass'
            - '.kdbx'
            - '.kdb'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium
regression_tests_path: regression_data/rules/windows/powershell/powershell_script/posh_ps_sensitive_file_discovery/info.yml

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_action

selection_action:
    ScriptBlockText|contains:
        - ls
        - get-childitem
        - gci

Stage 2: selection_recurse

selection_recurse:
    ScriptBlockText|contains: '-recurse'

Stage 3: selection_file

selection_file:
    ScriptBlockText|contains:
        - '.pass'
        - '.kdbx'
        - '.kdb'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
ScriptBlockTextmatch
  • -recurse
  • .kdb
  • .kdbx
  • .pass
  • gci
  • get-childitem corpus 4 (sigma 4)
  • ls corpus 2 (sigma 2)
field:"ScriptBlockText" kind:match

RDP shadow session started (command)

#
Status
experimental
Severity
high
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker would attempt to shadow a RDP session.

Known False Positives

  • administrative source host used for shadowing

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: RDP shadow session started (command)
description: Detects scenarios where an attacker would attempt to shadow a RDP session.
references:
- http://woshub.com/rds-shadow-how-to-connect-to-a-user-session-in-windows-server-2012-r2/
- https://www.elastic.co/guide/en/security/current/potential-remote-desktop-shadowing-activity.html
- https://bitsadm.in/blog/spying-on-users-using-rdp-shadowing
- https://swarm.ptsecurity.com/remote-desktop-services-shadowing/
tags:
- attack.lateral_movement
- attack.t1021.001 # remote services: RDP
- attack.collection
- attack.t1113 # screen capture
- attack.t1125 # video capture
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  category: process_creation
detection: # full command: mstsc /shadow:1 /v:<computer_name> /control /noConsentPrompt
  selection:
    NewProcessName|endswith: \mstsc.exe
    CommandLine|contains|all:
    - mstsc
    - '/shadow'
  condition: selection
falsepositives:
- administrative source host used for shadowing
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
  NewProcessName|endswith: \mstsc.exe
  CommandLine|contains|all:
  - mstsc
  - '/shadow'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • /shadow
  • mstsc
field:"CommandLine" kind:match
NewProcessNameends_with
  • \mstsc.exe corpus 6 (sigma 6)
field:"Image" kind:ends_with value:"\mstsc.exe"

Remote Access Tool - AnyDesk Incoming Connection

#
Status
experimental
Severity
medium
Author
@d4ns4n_ (Wuerth-Phoenix)
Source
github.com/SigmaHQ/sigma

Detects incoming connections to AnyDesk. This could indicate a potential remote attacker trying to connect to a listening instance of AnyDesk and use it as potential command and control channel.

Known False Positives

  • Legitimate incoming connections (e.g. sysadmin activity). Most of the time I would expect outgoing connections (initiated locally).

MITRE ATT&CK Coverage

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 3: Network connection

Rule Body

title: Remote Access Tool - AnyDesk Incoming Connection
id: d58ba5c6-0ed7-4b9d-a433-6878379efda9
status: experimental
description: |
    Detects incoming connections to AnyDesk. This could indicate a potential remote attacker trying to connect to a listening instance of AnyDesk and use it as potential command and control channel.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1219/T1219.md#atomic-test-2---anydesk-files-detected-test-on-windows
    - https://asec.ahnlab.com/en/40263/
author: '@d4ns4n_ (Wuerth-Phoenix)'
date: 2024-09-02
modified: 2025-02-24
tags:
    - attack.persistence
    - attack.command-and-control
    - attack.t1219.002
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        Image|endswith:
            - '\AnyDesk.exe'
            - '\AnyDeskMSI.exe'
        Initiated: 'false' # If the network connection is initiated remotely (incoming), the field is set to false.
    condition: selection
falsepositives:
    - Legitimate incoming connections (e.g. sysadmin activity). Most of the time I would expect outgoing connections (initiated locally).
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith:
        - '\AnyDesk.exe'
        - '\AnyDeskMSI.exe'
    Initiated: 'false'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageends_with
  • \AnyDesk.exe corpus 5 (sigma 5)
  • \AnyDeskMSI.exe corpus 4 (sigma 4)
field:"Image" kind:ends_with
Initiatedeq
  • false
field:"Initiated" kind:eq value:"false"

Ruby on Rails Framework Exceptions

#
Status
stable
Severity
medium
Author
Thomas Patzke
Source
github.com/SigmaHQ/sigma

Detects suspicious Ruby on Rails exceptions that could indicate exploitation attempts

Known False Positives

  • Application bugs

MITRE ATT&CK Coverage

TacticTechniques
Initial Access

Rule Body

title: Ruby on Rails Framework Exceptions
id: 0d2c3d4c-4b48-4ac3-8f23-ea845746bb1a
status: stable
description: Detects suspicious Ruby on Rails exceptions that could indicate exploitation attempts
references:
    - http://edgeguides.rubyonrails.org/security.html
    - http://guides.rubyonrails.org/action_controller_overview.html
    - https://stackoverflow.com/questions/25892194/does-rails-come-with-a-not-authorized-exception
    - https://github.com/rails/rails/blob/cd08e6bcc4cd8948fe01e0be1ea0c7ca60373a25/actionpack/lib/action_dispatch/middleware/exception_wrapper.rb
author: Thomas Patzke
date: 2017-08-06
modified: 2020-09-01
tags:
    - attack.initial-access
    - attack.t1190
logsource:
    category: application
    product: ruby_on_rails
detection:
    keywords:
        - ActionController::InvalidAuthenticityToken
        - ActionController::InvalidCrossOriginRequest
        - ActionController::MethodNotAllowed
        - ActionController::BadRequest
        - ActionController::ParameterMissing
    condition: keywords
falsepositives:
    - Application bugs
level: medium

Stages and Predicates

Stage 0: condition

keywords

Stage 1: keywords

keywords:
    - ActionController::InvalidAuthenticityToken
    - ActionController::InvalidCrossOriginRequest
    - ActionController::MethodNotAllowed
    - ActionController::BadRequest
    - ActionController::ParameterMissing

Screen Capture - macOS

#
Status
test
Severity
low
Author
remotephone, oscd.community
Source
github.com/SigmaHQ/sigma

Detects attempts to use screencapture to collect macOS screenshots

Known False Positives

  • Legitimate user activity taking screenshots

MITRE ATT&CK Coverage

TacticTechniques
Collection

Telemetry Coverage

Rule Body

title: Screen Capture - macOS
id: 0877ed01-da46-4c49-8476-d49cdd80dfa7
status: test
description: Detects attempts to use screencapture to collect macOS screenshots
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1113/T1113.md
    - https://github.com/EmpireProject/Empire/blob/08cbd274bef78243d7a8ed6443b8364acd1fc48b/lib/modules/python/collection/osx/screenshot.py
author: remotephone, oscd.community
date: 2020-10-13
modified: 2021-11-27
tags:
    - attack.collection
    - attack.t1113
logsource:
    product: macos
    category: process_creation
detection:
    selection:
        Image: '/usr/sbin/screencapture'
    condition: selection
falsepositives:
    - Legitimate user activity taking screenshots
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image: '/usr/sbin/screencapture'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Imageeq
  • /usr/sbin/screencapture
field:"Image" kind:eq value:"/usr/sbin/screencapture"

Steganography Extract Files with Steghide

#
Status
test
Severity
low
Author
Pawel Mazur
Source
github.com/SigmaHQ/sigma

Detects extraction of files with usage of steghide binary, the adversaries may use this technique to prevent the detection of hidden information.

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: Steganography Extract Files with Steghide
id: a5a827d9-1bbe-4952-9293-c59d897eb41b
status: test
description: Detects extraction of files with usage of steghide binary, the adversaries may use this technique to prevent the detection of hidden information.
references:
    - https://vitux.com/how-to-hide-confidential-files-in-images-on-debian-using-steganography/
author: 'Pawel Mazur'
date: 2021-09-11
modified: 2022-10-09
tags:
    - attack.stealth
    - attack.t1027.003
logsource:
    product: linux
    service: auditd
detection:
    selection:
        type: EXECVE
        a0: steghide
        a1: extract
        a2: '-sf'
        a3|endswith:
            - '.jpg'
            - '.png'
    condition: selection
falsepositives:
    - Unknown
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    type: EXECVE
    a0: steghide
    a1: extract
    a2: '-sf'
    a3|endswith:
        - '.jpg'
        - '.png'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
a0eq
  • steghide corpus 2 (sigma 2)
field:"a0" kind:eq value:"steghide"
a1eq
  • extract
field:"a1" kind:eq value:"extract"
a2eq
  • -sf
field:"a2" kind:eq value:"-sf"
a3ends_with
  • .jpg corpus 2 (sigma 2)
  • .png corpus 2 (sigma 2)
field:"a3" kind:ends_with
typeeq
  • EXECVE corpus 37 (sigma 31, splunk 6)
field:"type" kind:eq value:"EXECVE"

Suspicious Non-Browser Network Communication With Google API

#
Status
experimental
Severity
medium
Author
Gavin Knapp
Source
github.com/SigmaHQ/sigma

Detects a non-browser process interacting with the Google API which could indicate the use of a covert C2 such as Google Sheet C2 (GC2-sheet)

Known False Positives

  • Legitimate applications communicating with the "googleapis.com" endpoints that are not already in the exclusion list. This is environmental dependent and requires further testing and tuning.

MITRE ATT&CK Coverage

TacticTechniques
Command & Control

Telemetry Coverage

ProviderRecord / event type
SysmonEvent ID 3: Network connection

Rule Body

title: Suspicious Non-Browser Network Communication With Google API
id: 7e9cf7b6-e827-11ed-a05b-0242ac120003
status: experimental
description: |
    Detects a non-browser process interacting with the Google API which could indicate the use of a covert C2 such as Google Sheet C2 (GC2-sheet)
references:
    - https://github.com/looCiprian/GC2-sheet
    - https://youtu.be/n2dFlSaBBKo
    - https://services.google.com/fh/files/blogs/gcat_threathorizons_full_apr2023.pdf
    - https://www.tanium.com/blog/apt41-deploys-google-gc2-for-attacks-cyber-threat-intelligence-roundup/
    - https://www.bleepingcomputer.com/news/security/hackers-abuse-google-command-and-control-red-team-tool-in-attacks/
author: Gavin Knapp
date: 2023-05-01
modified: 2025-02-22
tags:
    - attack.command-and-control
    - attack.t1102
logsource:
    product: windows
    category: network_connection
detection:
    selection:
        DestinationHostname|contains:
            # Note: Please add additional google API related domains that might be abused.
            - 'drive.googleapis.com'
            - 'oauth2.googleapis.com'
            - 'sheets.googleapis.com'
            - 'www.googleapis.com'
    filter_optional_brave:
        Image|endswith: '\brave.exe'
    filter_optional_chrome:
        Image|endswith:
            - ':\Program Files\Google\Chrome\Application\chrome.exe'
            - ':\Program Files (x86)\Google\Chrome\Application\chrome.exe'
    filter_optional_google_drive:
        Image|contains: ':\Program Files\Google\Drive File Stream\'
        Image|endswith: '\GoogleDriveFS.exe'
    filter_optional_firefox:
        Image|endswith:
            - ':\Program Files\Mozilla Firefox\firefox.exe'
            - ':\Program Files (x86)\Mozilla Firefox\firefox.exe'
    filter_optional_ie:
        Image|endswith:
            - ':\Program Files (x86)\Internet Explorer\iexplore.exe'
            - ':\Program Files\Internet Explorer\iexplore.exe'
    filter_optional_maxthon:
        Image|endswith: '\maxthon.exe'
    filter_optional_edge_1:
        - Image|contains: ':\Program Files (x86)\Microsoft\EdgeWebView\Application\'
        - Image|endswith:
              - ':\Program Files (x86)\Microsoft\Edge\Application\msedge.exe'
              - ':\Program Files\Microsoft\Edge\Application\msedge.exe'
              - '\WindowsApps\MicrosoftEdge.exe'
    filter_optional_edge_2:
        Image|contains:
            - ':\Program Files (x86)\Microsoft\EdgeCore\'
            - ':\Program Files\Microsoft\EdgeCore\'
        Image|endswith:
            - '\msedge.exe'
            - '\msedgewebview2.exe'
    filter_optional_opera:
        Image|endswith: '\opera.exe'
    filter_optional_safari:
        Image|endswith: '\safari.exe'
    filter_optional_seamonkey:
        Image|endswith: '\seamonkey.exe'
    filter_optional_vivaldi:
        Image|endswith: '\vivaldi.exe'
    filter_optional_whale:
        Image|endswith: '\whale.exe'
    filter_optional_googleupdate:
        Image|endswith: '\GoogleUpdate.exe'
    filter_optional_outlook_exe:
        Image|endswith: '\outlook.exe'
    filter_main_null:
        Image: null
    filter_main_empty:
        Image: ''
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Legitimate applications communicating with the "googleapis.com" endpoints that are not already in the exclusion list. This is environmental dependent and requires further testing and tuning.
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:
    DestinationHostname|contains:
        - 'drive.googleapis.com'
        - 'oauth2.googleapis.com'
        - 'sheets.googleapis.com'
        - 'www.googleapis.com'

Stage 2: not filter_main_*

filter_main_null:
    Image: null
filter_main_empty:
    Image: ''

Stage 3: not filter_optional_*

filter_optional_brave:
    Image|endswith: '\brave.exe'
filter_optional_chrome:
    Image|endswith:
        - ':\Program Files\Google\Chrome\Application\chrome.exe'
        - ':\Program Files (x86)\Google\Chrome\Application\chrome.exe'
filter_optional_google_drive:
    Image|contains: ':\Program Files\Google\Drive File Stream\'
    Image|endswith: '\GoogleDriveFS.exe'
filter_optional_firefox:
    Image|endswith:
        - ':\Program Files\Mozilla Firefox\firefox.exe'
        - ':\Program Files (x86)\Mozilla Firefox\firefox.exe'
filter_optional_ie:
    Image|endswith:
        - ':\Program Files (x86)\Internet Explorer\iexplore.exe'
        - ':\Program Files\Internet Explorer\iexplore.exe'
filter_optional_maxthon:
    Image|endswith: '\maxthon.exe'
filter_optional_edge_1:
    - Image|contains: ':\Program Files (x86)\Microsoft\EdgeWebView\Application\'
    - Image|endswith:
          - ':\Program Files (x86)\Microsoft\Edge\Application\msedge.exe'
          - ':\Program Files\Microsoft\Edge\Application\msedge.exe'
          - '\WindowsApps\MicrosoftEdge.exe'
filter_optional_edge_2:
    Image|contains:
        - ':\Program Files (x86)\Microsoft\EdgeCore\'
        - ':\Program Files\Microsoft\EdgeCore\'
    Image|endswith:
        - '\msedge.exe'
        - '\msedgewebview2.exe'
filter_optional_opera:
    Image|endswith: '\opera.exe'
filter_optional_safari:
    Image|endswith: '\safari.exe'
filter_optional_seamonkey:
    Image|endswith: '\seamonkey.exe'
filter_optional_vivaldi:
    Image|endswith: '\vivaldi.exe'
filter_optional_whale:
    Image|endswith: '\whale.exe'
filter_optional_googleupdate:
    Image|endswith: '\GoogleUpdate.exe'
filter_optional_outlook_exe:
    Image|endswith: '\outlook.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
DestinationHostnamematch
  • drive.googleapis.com
  • oauth2.googleapis.com
  • sheets.googleapis.com
  • www.googleapis.com
field:"DestinationHostname" kind:match

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imageis_null(no value, null check)excludes:Image
Imageends_with\msedge.exeexcludes:Image field:"Image" value:"\msedge.exe"
Imageends_with\msedgewebview2.exeexcludes:Image field:"Image" value:"\msedgewebview2.exe"
Imagematch:\Program Files (x86)\Microsoft\EdgeCore\excludes:Image field:"Image" value:":\Program Files (x86)\Microsoft\EdgeCore\"
Imagematch:\Program Files\Microsoft\EdgeCore\excludes:Image field:"Image" value:":\Program Files\Microsoft\EdgeCore\"
Imageends_with\GoogleDriveFS.exeexcludes:Image field:"Image" value:"\GoogleDriveFS.exe"
Imagematch:\Program Files\Google\Drive File Stream\excludes:Image field:"Image" value:":\Program Files\Google\Drive File Stream\"
Imageends_with:\Program Files (x86)\Google\Chrome\Application\chrome.exeexcludes:Image field:"Image" value:":\Program Files (x86)\Google\Chrome\Application\chrome.exe"
Imageends_with:\Program Files (x86)\Internet Explorer\iexplore.exeexcludes:Image field:"Image" value:":\Program Files (x86)\Internet Explorer\iexplore.exe"
Imageends_with:\Program Files (x86)\Microsoft\Edge\Application\msedge.exeexcludes:Image field:"Image" value:":\Program Files (x86)\Microsoft\Edge\Application\msedge.exe"
Imageends_with:\Program Files (x86)\Mozilla Firefox\firefox.exeexcludes:Image field:"Image" value:":\Program Files (x86)\Mozilla Firefox\firefox.exe"
Imageends_with:\Program Files\Google\Chrome\Application\chrome.exeexcludes:Image field:"Image" value:":\Program Files\Google\Chrome\Application\chrome.exe"
Imageends_with:\Program Files\Internet Explorer\iexplore.exeexcludes:Image field:"Image" value:":\Program Files\Internet Explorer\iexplore.exe"
Imageends_with:\Program Files\Microsoft\Edge\Application\msedge.exeexcludes:Image field:"Image" value:":\Program Files\Microsoft\Edge\Application\msedge.exe"
Imageends_with:\Program Files\Mozilla Firefox\firefox.exeexcludes:Image field:"Image" value:":\Program Files\Mozilla Firefox\firefox.exe"
Imageends_with\GoogleUpdate.exeexcludes:Image field:"Image" value:"\GoogleUpdate.exe"
Imageends_with\WindowsApps\MicrosoftEdge.exeexcludes:Image field:"Image" value:"\WindowsApps\MicrosoftEdge.exe"
Imageends_with\brave.exeexcludes:Image field:"Image" value:"\brave.exe"
Imageends_with\maxthon.exeexcludes:Image field:"Image" value:"\maxthon.exe"
Imageends_with\opera.exeexcludes:Image field:"Image" value:"\opera.exe"
Imageends_with\outlook.exeexcludes:Image field:"Image" value:"\outlook.exe"
Imageends_with\safari.exeexcludes:Image field:"Image" value:"\safari.exe"
Imageends_with\seamonkey.exeexcludes:Image field:"Image" value:"\seamonkey.exe"
Imageends_with\vivaldi.exeexcludes:Image field:"Image" value:"\vivaldi.exe"
Imageends_with\whale.exeexcludes:Image field:"Image" value:"\whale.exe"
Imagematch:\Program Files (x86)\Microsoft\EdgeWebView\Application\excludes:Image field:"Image" value:":\Program Files (x86)\Microsoft\EdgeWebView\Application\"

Troubleshooting Pack Cmdlet Execution

#
Status
test
Severity
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects execution of "TroubleshootingPack" cmdlets to leverage CVE-2022-30190 or action similar to "msdt" lolbin (as described in LOLBAS)

Known False Positives

  • Legitimate usage of "TroubleshootingPack" cmdlet for troubleshooting purposes

MITRE ATT&CK Coverage

TacticTechniques
Stealth

Telemetry Coverage

Rule Body

title: Troubleshooting Pack Cmdlet Execution
id: 03409c93-a7c7-49ba-9a4c-a00badf2a153
status: test
description: Detects execution of "TroubleshootingPack" cmdlets to leverage CVE-2022-30190 or action similar to "msdt" lolbin (as described in LOLBAS)
references:
    - https://twitter.com/nas_bench/status/1537919885031772161
    - https://lolbas-project.github.io/lolbas/Binaries/Msdt/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-06-21
tags:
    - attack.stealth
    - attack.t1202
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        ScriptBlockText|contains|all:
            - 'Invoke-TroubleshootingPack'
            - 'C:\Windows\Diagnostics\System\PCW'
            - '-AnswerFile'
            - '-Unattended'
    condition: selection
falsepositives:
    - Legitimate usage of "TroubleshootingPack" cmdlet for troubleshooting purposes
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    ScriptBlockText|contains|all:
        - 'Invoke-TroubleshootingPack'
        - 'C:\Windows\Diagnostics\System\PCW'
        - '-AnswerFile'
        - '-Unattended'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
ScriptBlockTextmatch
  • -AnswerFile
  • -Unattended
  • C:\Windows\Diagnostics\System\PCW
  • Invoke-TroubleshootingPack
field:"ScriptBlockText" kind:match

VBScript Payload Stored in Registry

#
Status
test
Severity
high
Author
Florian Roth (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects VBScript content stored into registry keys as seen being used by UNC2452 group

MITRE ATT&CK Coverage

Telemetry Coverage

Rule Body

title: VBScript Payload Stored in Registry
id: 46490193-1b22-4c29-bdd6-5bf63907216f
status: test
description: Detects VBScript content stored into registry keys as seen being used by UNC2452 group
references:
    - https://www.microsoft.com/security/blog/2021/03/04/goldmax-goldfinder-sibot-analyzing-nobelium-malware/
author: Florian Roth (Nextron Systems)
date: 2021-03-05
modified: 2023-08-17
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1547.001
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion'
        Details|contains:
            - 'vbscript:'
            - 'jscript:'
            - 'mshtml,'
            - 'RunHTMLApplication'
            - 'Execute('
            - 'CreateObject'
            - 'window.close'
    filter:
        TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion\Run'
    filter_dotnet:
        Image|endswith: '\msiexec.exe'
        TargetObject|contains: '\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\'
        Details|contains:
            - '\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll'
            - '<\Microsoft.mshtml,fileVersion='
            - '_mshtml_dll_'
            - '<\Microsoft.mshtml,culture='
    condition: selection and not 1 of filter*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection and not 1 of filter*

Stage 1: selection

selection:
    TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion'
    Details|contains:
        - 'vbscript:'
        - 'jscript:'
        - 'mshtml,'
        - 'RunHTMLApplication'
        - 'Execute('
        - 'CreateObject'
        - 'window.close'

Stage 2: not filter*

filter:
    TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion\Run'
filter_dotnet:
    Image|endswith: '\msiexec.exe'
    TargetObject|contains: '\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\'
    Details|contains:
        - '\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll'
        - '<\Microsoft.mshtml,fileVersion='
        - '_mshtml_dll_'
        - '<\Microsoft.mshtml,culture='

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Detailsmatch
  • CreateObject
  • Execute(
  • RunHTMLApplication
  • jscript:
  • mshtml,
  • vbscript:
  • window.close
field:"Details" kind:match
TargetObjectmatch
  • Software\Microsoft\Windows\CurrentVersion
field:"TargetObject" kind:match value:"Software\Microsoft\Windows\CurrentVersion"

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Detailsmatch<\Microsoft.mshtml,culture=excludes:Details field:"Details" value:"<\Microsoft.mshtml,culture="
Detailsmatch<\Microsoft.mshtml,fileVersion=excludes:Details field:"Details" value:"<\Microsoft.mshtml,fileVersion="
Detailsmatch\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dllexcludes:Details field:"Details" value:"\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll"
Detailsmatch_mshtml_dll_excludes:Details field:"Details" value:"_mshtml_dll_"
Imageends_with\msiexec.exeexcludes:Image field:"Image" value:"\msiexec.exe"
TargetObjectmatch\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\excludes:TargetObject field:"TargetObject" value:"\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\"
TargetObjectmatchSoftware\Microsoft\Windows\CurrentVersion\Runexcludes:TargetObject field:"TargetObject" value:"Software\Microsoft\Windows\CurrentVersion\Run"

Webshell ReGeorg Detection Via Web Logs

#
Status
test
Severity
high
Author
Cian Heasley
Source
github.com/SigmaHQ/sigma

Certain strings in the uri_query field when combined with null referer and null user agent can indicate activity associated with the webshell ReGeorg.

Known False Positives

  • Web applications that use the same URL parameters as ReGeorg

MITRE ATT&CK Coverage

Rule Body

title: Webshell ReGeorg Detection Via Web Logs
id: 2ea44a60-cfda-11ea-87d0-0242ac130003
status: test
description: Certain strings in the uri_query field when combined with null referer and null user agent can indicate activity associated with the webshell ReGeorg.
references:
    - https://community.rsa.com/community/products/netwitness/blog/2019/02/19/web-shells-and-netwitness-part-3
    - https://github.com/sensepost/reGeorg
author: Cian Heasley
date: 2020-08-04
modified: 2023-01-02
tags:
    - attack.persistence
    - attack.t1505.003
logsource:
    category: webserver
detection:
    selection:
        cs-uri-query|contains:
            - 'cmd=read'
            - 'connect&target'
            - 'cmd=connect'
            - 'cmd=disconnect'
            - 'cmd=forward'
    filter:
        cs-referer: null
        cs-user-agent: null
        cs-method: POST
    condition: selection and filter
falsepositives:
    - Web applications that use the same URL parameters as ReGeorg
level: high

Stages and Predicates

Stage 0: condition

selection and filter

Stage 1: selection

selection:
    cs-uri-query|contains:
        - 'cmd=read'
        - 'connect&target'
        - 'cmd=connect'
        - 'cmd=disconnect'
        - 'cmd=forward'

Stage 2: filter

filter:
    cs-referer: null
    cs-user-agent: null
    cs-method: POST

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
cs-methodeq
  • POST
field:"cs-method" kind:eq value:"POST"
cs-refereris_null
  • (no value, null check)
field:"cs-referer" kind:is_null
cs-uri-querymatch
  • cmd=connect
  • cmd=disconnect
  • cmd=forward
  • cmd=read
  • connect&target
field:"cs-uri-query" kind:match
cs-user-agentis_null
  • (no value, null check)
field:"cs-user-agent" kind:is_null

Winget Admin Settings Modification

#
Status
test
Severity
low
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects changes to the AppInstaller (winget) admin settings. Such as enabling local manifest installations or disabling installer hash checks

Known False Positives

  • The event doesn't contain information about the type of change. False positives are expected with legitimate changes

MITRE ATT&CK Coverage

TacticTechniques
PersistenceNo specific technique
Defense ImpairmentNo specific technique

Telemetry Coverage

Rule Body

title: Winget Admin Settings Modification
id: 6db5eaf9-88f7-4ed9-af7d-9ef2ad12f236
status: test
description: Detects changes to the AppInstaller (winget) admin settings. Such as enabling local manifest installations or disabling installer hash checks
references:
    - https://github.com/nasbench/Misc-Research/tree/b9596e8109dcdb16ec353f316678927e507a5b8d/LOLBINs/Winget
    - https://github.com/microsoft/winget-cli/blob/02d2f93807c9851d73eaacb4d8811a76b64b7b01/src/AppInstallerCommonCore/Public/winget/AdminSettings.h#L13
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-04-17
modified: 2023-08-17
tags:
    - attack.persistence
    - attack.defense-impairment
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        Image|endswith: '\winget.exe'
        TargetObject|startswith: '\REGISTRY\A\'
        TargetObject|endswith: '\LocalState\admin_settings'
    condition: selection
falsepositives:
    - The event doesn't contain information about the type of change. False positives are expected with legitimate changes
level: low

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    Image|endswith: '\winget.exe'
    TargetObject|startswith: '\REGISTRY\A\'
    TargetObject|endswith: '\LocalState\admin_settings'

Indicators

These rows show field, operator, and value matches.

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