title: UAC Bypass Using Registry Shell Open Keys
author: Christian Burkard
date: 2021/08/30
description: Detects the pattern of UAC Bypass using fodhelper.exe, computerdefaults.exe,
    slui.exe via registry keys (e.g. UACMe 33 or 62)
detection:
    SELECTION_1:
        EventID: 12
    SELECTION_10:
        TargetObject: '*Classes\ms-settings\shell\open\command\(Default)'
    SELECTION_11:
        TargetObject: '*Classes\exefile\shell\open\command\(Default)'
    SELECTION_12:
        Details: (Empty)
    SELECTION_2:
        EventID: 13
    SELECTION_3:
        EventID: 14
    SELECTION_4:
        TargetObject: '*Classes\ms-settings\shell\open\command\SymbolicLinkValue'
    SELECTION_5:
        Details: '*\Software\Classes\{*'
    SELECTION_6:
        TargetObject: '*Classes\ms-settings\shell\open\command\DelegateExecute'
    SELECTION_7:
        EventID: 12
    SELECTION_8:
        EventID: 13
    SELECTION_9:
        EventID: 14
    condition: ((SELECTION_1 or SELECTION_2 or SELECTION_3) and (((SELECTION_4 and
        SELECTION_5) or SELECTION_6) or ((SELECTION_7 or SELECTION_8 or SELECTION_9)
        and (SELECTION_10 or SELECTION_11) and  not (SELECTION_12))))
falsepositives:
- Unknown
id: 152f3630-77c1-4284-bcc0-4cc68ab2f6e7
level: high
logsource:
    category: registry_event
    product: windows
modified: 2021/09/17
references:
- https://github.com/hfiref0x/UACME
- https://winscripting.blog/2017/05/12/first-entry-welcome-and-uac-bypass/
- https://github.com/RhinoSecurityLabs/Aggressor-Scripts/tree/master/UACBypass
status: experimental
tags:
- attack.defense_evasion
- attack.privilege_escalation
- attack.t1548.002
yml_filename: sysmon_uac_bypass_shell_open.yml
yml_path: /Users/user/Documents/YamatoSecurity/sigma/rules/windows/registry_event