title: Regedit as Trusted Installer
id: 883835a7-df45-43e4-bf1d-4268768afda4
status: test
description: Detects a regedit started with TrustedInstaller privileges or by ProcessHacker.exe
references:
    - https://twitter.com/1kwpeter/status/1397816101455765504
author: Florian Roth (Nextron Systems)
date: 2021-05-27
modified: 2022-10-09
tags:
    - attack.privilege-escalation
    - attack.t1548
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\regedit.exe'
        ParentImage|endswith:
            - '\TrustedInstaller.exe'
            - '\ProcessHacker.exe'
    condition: selection
falsepositives:
    - Unlikely
level: high

title: Suspicious Installer Package Child Process
id: e0cfaecd-602d-41af-988d-f6ccebb2af26
status: test
description: Detects the execution of suspicious child processes from macOS installer package parent process. This includes osascript, JXA, curl and wget amongst other interpreters
references:
    - https://redcanary.com/blog/clipping-silver-sparrows-wings/
    - https://github.com/elastic/detection-rules/blob/4312d8c9583be524578a14fe6295c3370b9a9307/rules/macos/execution_installer_package_spawned_network_event.toml
author: Sohan G (D4rkCiph3r)
date: 2023-02-18
tags:
    - attack.t1059
    - attack.t1059.007
    - attack.t1071
    - attack.t1071.001
    - attack.execution
    - attack.command-and-control
logsource:
    category: process_creation
    product: macos
detection:
    selection_installer:
        ParentImage|endswith:
            - '/package_script_service'
            - '/installer'
        Image|endswith:
            - '/sh'
            - '/bash'
            - '/dash'
            - '/python'
            - '/ruby'
            - '/perl'
            - '/php'
            - '/javascript'
            - '/osascript'
            - '/tclsh'
            - '/curl'
            - '/wget'
        CommandLine|contains:
            - 'preinstall'
            - 'postinstall'
    condition: selection_installer
falsepositives:
    - Legitimate software uses the scripts (preinstall, postinstall)
level: medium

title: Tap Installer Execution
id: 99793437-3e16-439b-be0f-078782cf953d
status: test
description: Well-known TAP software installation. Possible preparation for data exfiltration using tunneling techniques
references:
    - https://community.openvpn.net/openvpn/wiki/ManagingWindowsTAPDrivers
author: Daniil Yugoslavskiy, Ian Davis, oscd.community
date: 2019-10-24
modified: 2023-12-11
tags:
    - attack.exfiltration
    - attack.t1048
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\tapinstall.exe'
    filter_optional_avast:
        Image|contains:
            - ':\Program Files\Avast Software\SecureLine VPN\'
            - ':\Program Files (x86)\Avast Software\SecureLine VPN\'
    filter_optional_openvpn:
        Image|contains: ':\Program Files\OpenVPN Connect\drivers\tap\'
    filter_optional_protonvpn:
        Image|contains: ':\Program Files (x86)\Proton Technologies\ProtonVPNTap\installer\'
    condition: selection and not 1 of filter_optional_*
falsepositives:
    - Legitimate OpenVPN TAP installation
level: medium

title: Always Install Elevated Windows Installer
id: cd951fdc-4b2f-47f5-ba99-a33bf61e3770
status: test
description: Detects Windows Installer service (msiexec.exe) trying to install MSI packages with SYSTEM privilege
references:
    - https://image.slidesharecdn.com/kheirkhabarovoffzonefinal-181117201458/95/hunting-for-privilege-escalation-in-windows-environment-48-638.jpg
author: Teymur Kheirkhabarov (idea), Mangatas Tondang (rule), oscd.community
date: 2020-10-13
modified: 2024-12-01
tags:
    - attack.privilege-escalation
    - attack.t1548.002
logsource:
    product: windows
    category: process_creation
detection:
    selection_user:
        User|contains: # covers many language settings
            - 'AUTHORI'
            - 'AUTORI'
    selection_image_1:
        Image|contains|all:
            - '\Windows\Installer\'
            - 'msi'
        Image|endswith: 'tmp'
    selection_image_2:
        Image|endswith: '\msiexec.exe'
        IntegrityLevel:
            - 'System'
            - 'S-1-16-16384'
    filter_installer:
        ParentImage: 'C:\Windows\System32\services.exe'
    filter_repair:
        - CommandLine|endswith: '\system32\msiexec.exe /V' # ignore "repair option"
        - ParentCommandLine|endswith: '\system32\msiexec.exe /V' # ignore "repair option"
    filter_sophos:
        ParentImage|startswith: 'C:\ProgramData\Sophos\'
    filter_avira:
        ParentImage|startswith: 'C:\ProgramData\Avira\'
    filter_avast:
        ParentImage|startswith:
            - 'C:\Program Files\Avast Software\'
            - 'C:\Program Files (x86)\Avast Software\'
    filter_google_update:
        ParentImage|startswith:
            - 'C:\Program Files\Google\Update\'
            - 'C:\Program Files (x86)\Google\Update\'
    condition: 1 of selection_image_* and selection_user and not 1 of filter_*
falsepositives:
    - System administrator usage
    - Anti virus products
    - WindowsApps located in "C:\Program Files\WindowsApps\"
level: medium